I had a wide selection and had fun when i was on Low Rank to High Rank. Don't rush the game so much, I know people love to say don't invest so much except when you're on G rank, but IMO you have the chance to experiment things early on; (Keep in mind I am also a CB main for this game)
Low Rank - Great Jaggi set first, great armor to use for a while, has speed sharpener if I remember correctly.
Tetsucabra - this armor is the ideal one if you want to breeze through low rank; easy to make and pretty much a tank in defense.
Seltas - I started experimenting at this point, and I LOVE artillery god, really helps with the impact phial damage and you'll notice it!
Brachydios - I experimented with blast status, so while I invested on the Dios CB initially, I ended up getting the armor too just to see how it's gonna be like with the bomb boost.
Gore Magala - I couldn't help but getting this one, I eventually had the parts to get it, it runs nice. The important part is to get the Gore CB, just because you want that dragon status for you to work with later on.
Cenataur (right spelling? wtever) - the only reason I tried these is because I wanted to see razor sharpness and sharpener together? It was nice that my weapons don't dull as quick, but in exchange of artillery, bomb boost and defense, i personally didn't feel good about it.
At this point I was also experimenting on what kind of style I liked when playing CB. I initially started using CB just for guard points really, so I got that down quick and started GP'ing everything and countering everything. I never even considered Guard skills because I associated them often with Lance...
High Rank - Black/ Gravios armor - I tried this out because when Tigrex or other monsters do a specific move, even on guard point I get pushed back. So I wondered if there's anything I could do with that and went and got Guard Up from Black Gravios and Guard +2 from regular Gravios. Guard Up did not sit well with me since it's just able to block unblockable attacks from before, so this wasn't the priority. But then I tried Guard +2 and everything fell on its place.
This is where I finally discovered what skills I would like on priority; Guard +2, Razor Sharpness, and Artillery God / Attack Up (L). My Gravios armor has 430+ defense at this point and I had several configurations with it depending on the hunt such as; (Guard+2, DefUp(L), KO), (Guard+2, DefUp(M),Gathering God), (Guard+2, DefUp(XL),Gourmand), (Guard+2, Wide-Range+2,DefUp(M))
I was able to find this Guard +2 work well with me because I go crazy with the guard points and counters and being on the guys face without even sheathing. I am also leaning towards fencing or razor sharpness now, because I see myself often bouncing. Also investing on a Nerscylla weapon for that sharpness. I just got to G rank but already I have discovered my playstyle and my preferred skills, and it's been a blast. Now I'm ready to take on tougher stuff on my prime condition.