vOverall, you guys had a great great lead in the early game. Diana was getting really strong in mid and would become a monster later on and Lucian was really far ahead of Jihn. There was serious potential for you guys to win this game. But, at about 8 minutes there were too many bad decisions that led to your lead whittling away. Especially, when Braum, Jihn, and Olaf managed to grab your turret and end lane phase. You guys didn't take the opportunities presented in front of you to grab key objectives. Also, your warding was mediocre. You didn't transition at all from lane phase into mid game; you tried staying bot with lucian and spent your pink ward near bot. Once lane phase is over, you are no longer Lucian's babysitter.
In terms of itemization, I think it was fine. let me walk you through my mindset in this game. For this game you are not really a pick-oriented champion because there aren't many people to hook, so you don't need that much MS. For that reason, I would change how you level up your abilities this game. During laning phase, play normally and max your Q, but once laning phase is over resort to maxing your E so you can maximize your CC. Your lucidity boots buy was also a nice choice for the CD. Still, just remember that swifties are definitely better on Blitz in most situations.
Below is the play-by-play. I'd suggest watching the game as you read through it. I commentate as I watch, so I don't know what will happen next. I also have Fog of War on:
0:00- Sweet Jesus. This game is going to be hell on earth for you. Garen and Braum are both champs you don't want to pull. Fizz and Olaf are people you can't CC even if you want to. Jihn is your only target. Lane looks super unappealing with the easy to land Braum/Jihn double stun. Roaming isn't much of an option here. Really bad spot for Blitz: you are gonna be a ward/aura/tank focusing on Exh Olaf, shielding Lucian, and hooking Jihn.
0:01- You have the option to invade with very little risk. I would try every single cheese in the book in this game to get the early lead. Try stealing blue buff from the jungler. Most junglers smite gromp, so you can just walk around to blue buff at 1:45 and steal it with hook.
2:09- No point in Exh here. There was no way you were gonna kill Jihn. Better to just switch to Braum b/c a longterm engage is in your favor: Braum is fighting in your creeps and Lucian has higher overtime damage at level 1 compared to Jihn.
2:28- Lucian didn't respect Jihn's 4th attack. I think you guys should have disengaged from the fight as soon as Jihn was out of range of Lucian's damage. He was low enough where you could pick and kill him later once you hit level 2.
3:22- This is an appropriate time to roam if you would like. If you are going to roam, then don't plant the pink ward down just yet.
4:01- You should be engaging on Braum or Jihn here. Even though Jihn is up a pickaxe, you have 8 creeps with you. It doesn't matter who you hook, just hook somebody.
4:30- Be careful of Olaf now. He hasn't showed anywhere yet and you are the lane to gank atm.
4:34- Well he shows top, so your good. Fizz is missing though, and he backed already. He could be coming for a bot gank (unlikely but you should ward regardless).
4:40-5:03- Good job here. This was played perfectly from what I can see.
5:05- Small mistake here. You walked backwards to try to protect Lucian, but he doesn't need your help (there are like 5 creeps helping him). You should be continuing to AA Jihn and only when he gets out of range should you switch back to Braum.
5:07- You run away after one AA on Braum. You could have landed 2 more. Every little thing counts in this lane. The lower their health is the higher your pick potential and the better you can zone.
5:11- Wow, if you AA'd Jihn before instead of getting off of him, it could have been possible for Lucian to pick up a kill.
5:39- Chances are because of his death top lane, Olaf will be more committed to farming the jungle than ganking. Still, where you guys are standing is 100% gankable if he wanted to come. He could very well be bot side since you have no vision. Tell Lucian to ward.
5:40- God dam, this is the 2nd time I pause right before vision of Olaf... Still you should be warding.
5:52-5:58- Why are you standing so far back? Olaf was seen at raptors and you have the advantage in the lane currently. You should be standing up front zoning Jihn from farm and waiting for a hook.
6:12- You shouldn't be fighting Olaf here. Lucian knowingly suicided for the kill, so you should peace out. I don't know why Olaf felt the need to ignore Braum's concussive blows, but you should have been dead here. You lived b/c of the enemy's mistake, not b/c you played it correctly.
7:00- I don't like the idea of getting another pink here. You have one placed already and you have sweeper now if Amumu wants to gank. I would grab a couple health pots. Why? Read the next comment.
7:02- You guys have a huge advantage in lane now. Lucain has BF compared to Jihn's Pickaxe. You can play this hyperaggr as long as you ward out Olaf. Get in as many trades as possible, b/c you will win them all. This is why you need pots to heal up. You should aim to make this lane very bloody.
7:33- You could have aimed your hook at Braum as well. Go for the easy hooks, b/c any hook is a win. You and Lucian's pressure right now is off the charts.
7:55- Here is what I would be thinking now. It looked like Olaf was heading for his blue, so there is a good chance he will gank bot, b/c once again you guys are the lane to gank. It is perfectly fine pushing this lane all the way to their tower, BUT you need to have wards far enough away so that you can react to a gank. If you get a ward at dragon, Olaf will never be able to gank you successfully.
8:24- Huge mistake by you and Lucian. You guys didn't respond to Amumu's invade fast enough. The fact that you guys let Braum walk their without engaging on him is bad. You should have been there to back him up b/c the fight is so in your favor. Gah, that fight would have completely gone in your favor if you guys responded a few seconds earlier.
9:04- What is that tp lol? He could have tp'd to a creep or that deep ward brush instead...
9:23- You guys should be pinging dragon right now. You can't take tower with Garen, Jihn, and Braum there but you can take Dragon.
9:40- Especially now that Braum is dead: you should be grabbing dragon; they can't contest you. Jihn ult is down.
11:01- There was no reason for you to go back into the fight. You had the perfect idea with engaging here, but you missed. So just sit back and wait for CDs. Jihn ends up making a mistake and takes too much harass, but that isn't a reason to misposition yourself. You have no way of closing the gap on Jihn b/c your Overdrive and hook are on CD.
11:33- Really bad choice in staying in lane. Olaf was just killing your pink at tri. Anyone with half a brain would stay and dive you.
12:36- Omg Naut.... That made me facepalm hard. He should have ran straight into lane. Instead he walks away dick in hand >.>
13:05- oooooooo that sucks sooo much. You guys played that so well too but Lucian mis-stepped slightly and got hit by tower. That should have been a 2 for 0 but ends up being a 1 for 2. Sad day. Also, you should mega ping Diana to grab mid tower.
14:26- Can't really blame you for staying. Even I would have fell for that greed; it looked so juicy. Still a mistake though.
14:40- Basically, you guys had such a good lead in lane, but it was thrown away from 5 things. You guys dying at level 1, you guys not responding to Amumu fast enough, you mispositioning in a fight against Jihn/Braum, you guys not taking dragon, and Lucain accidentally taking a tower shot. There were other errors I mentioned, but these were the big ones. Also, your warding was pretty subpar. There were a few times in lane that ganks were a possible threat, but you guys had no or limited vision. Now that laning phase is over, your job becomes 10x harder.
15:20- Tell Lucian to grab that tower. He has no reason to back off.
16:10- It is time to step your warding game up. That ward is useless; it won't detect people until it is too late. Throw a ward near their blue buff. Let Lucian farm bot alone and ward out botside
16:30- Next major objectives for the taking is Rift Herald. If the enemy team gets it, then they can grab towers. You need to avoid this by warding that area.
17:11- This isn't laning phase anymore. You don't need to pink the tri. There are more important areas to ward like river and their blue buff and Rift Herald. As long as you ward for Lucian, you don't need to be there to babysit him. You should be moving more globally threatening objectives.
17:52- Tell Lucian to keep pushing. It looks like the enemy is at Rift Herald. Be careful of ganking mid, it will turn out a 5v4.
18:00- You guys are chasing so far and for a Fizz that will trickster away. Diana wasn't close to you guys and Lucian was back. Really bad engage.
18:30- You engaged again without your team. Not very pretty on your part.
19:15- Your usefulness as a hooker has gone out the window. It is that point in the game that you are a ward bot/tank/aura/shielder. You can't even CC the assassins here. Play the macro game to win. Games not lookin very nice atm. You are also level 8 b/c of all your deaths and don't have oracles which really hurts your team's antivision.
19:50- Why are you near baron? Rift was taken and they can't Baron right now. You should be at dragon warding. Your team even pinged it yet you and Diana are near topside. This will most likely cost you a drag b/c now it is too dangerous to ward.
20:30- Amumu saved you guys, but still that was a mistake on your part for going top and not warding near drag. Also, if I was the enemy team I would be going for baron.