Opponent is one of the better regulars, that I generally try to avoid. He is running at 21/17. Relatively aggressive. Also running at 14 BB/100 over 1000 hands.

I have been fairly active over my 60 hands at the table, running at 30/22. But I just folded to a 3 bet a few times.
He starts the hand with 950, and I have 875

I pick up in the CO and raise to 21, he repops me from the SB to 70.
I just calls to disguise my hand (it gets pretty obvious if I 4 bet - there hasn't been one 4 bet at the table yet) and play it in position.

Flop (146)
He checks, I check behind.
He is CBing a lot. 80% of his hands.

Turn (146)
He bets 100, I call

River (346)
He checks, I bet 150

Did I play this too passively? Input on all streets please.

Why are you checking behind on that flop with AA? I prefer a bet as QQ/KK/AJ call.

Turn, I don't mind the call.

River I don't mind the bet, but is he the type that would CR big there wtih AK (i.e., pretty aggressive on the river)?

By the end of the hand I'm wishing you had raised on some street.

Hard to advice on hand which depends a lot on the dynamics, how often he 3-bets for example?

Still my first choice would be 4-bet preflop. I don't mind your postflop play, as you got a bad flop.

I'll call here PF to alot of the time.
When he doesn't CB I think we can exclude KK,QQ from his range, JJ is possible. AK SHOULD CB here a lot since AK can't call a flop bet, weird flop action. I can see him having TT here.
I like the turn call I think he's just taking a stab at it.
When he checks river I think he has given up the hand, sure AK could have hit but AK should have CB that flop.