So, you would like an opening with black that allows you to retain the two bishops, avoid a cramped position, be free from any pawn weaknesses, and yet doesn't have an excessive amount of theory! Sounds simple enough!
For the bishop i just would like not to trade it early in the game for a knight, it's psychological i guess. Of course i won't keep it just for the sake of keeping it during the game.
I've to reread my first post (sorry i'm on my phone it's hard) but i didn't recall wanting "no pawn weakness".
And for the theory you're partly right. Just would like to avoid, if possible, the heavy theory of opening of the like of the Grunfeld (from what i heard) and the semi-slav
For the cramped position you're right
You've played a whole bunch of openings, change after a bit of experience and then start again. I'm thinking the problem isn't the openings.
Not that much
For black i only studied and played the benko (which often didn't get there since a lot of players play Nf3 or even b3 on response to b5). But even though it's dynamic i found it hard to play once a player had some idea how to deal with it. It's better for blitz or rapid.

And for black i exclusively play the caro kann.
as white i did change from london, to classical d4-c4 and now (with some success) the english that i like. Neven played 1.e4 before
But for sure you're right that my opening shouldn't be my main concern, I want to create a opening repertoire that i can review before an official OTB match with my club (which starts in september). Once i've build a good enough of a repertoire i'll switch my attention again on what was my previous training plan: Tactic, tactic, tactic, annotated GM games and some endgames.