1.Less mechanics to learn, multi tasking with more things to consider when you play (turn rates, enemy heroes, denying/farming, looking for oppurtunities to help allies via tp to lanes, runes, real invisibility heroes, global pressence of heroes which on LoL was completely gutted, overall gameplay offers much more tools (items with actives like blink daggers, force staffs, euls/sheep/orchid/bkbs etc. etc. and also consumables like smokes/dust/sentries. Also to add up more ability to help your allies like throwing ally with toss when he's escaping, salving ally, sharing tangos, refilling ally's hp/mana with bottle sharing.. A lot to say, just giving random examples). To add up DotA have actual uniqueness for whole roster while keeping 107 heroes in balanced/viable state unlike LoL. Do I need to say more?
2. They actually care, Valve helped a lot of times with some bigger issues regarding players (like Fnatic Era's injury just before TI4), DotA 2 client supports fully tourmaments with ticket system and DotA TV in general, they fix most bugs, which show up after patch ASAP, which is important. Valve just don't show up to brag up their asses like Riot so they can take all the glory (Valve is more of Santa's little helper if you know what I mean). Also they helped a lot in grow of eSports without taking credit for it
3. /r/DotA2 showed up propably when first closed beta invites were sent. Basically only few people got them and then that spread to more people. Not sure, but maybe back then DotA 2 was on alpha (haven't played, got beta invite from friend quite a while ago like 2012 or something), but official release was kind of late.
4. It's a matter of artstyle, but I would say design of LoL's female champs is more about sexappeal (Morello even once said on official LoL forums that model doesn't look like female when they have smaller tits than D cups and more like metrosexual boy).
Btw this Vengeful Spirit's pic is just silly, she just have fit outfit not goddamm Pamela Anderson's boobs coming out from the corset shaped chest, don't try digging too hard, cuz you'll find some nasty shit waiting for you deeper : )