Getting value on a scary board

Opponent is a nit but I don't like folding preflop. He is 17/6/3 atm. I've been pretty active on this table.

PokerStars No-Limit Hold'em, $0.50 BB (6 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

Button ($25.35)
SB ($46)
Hero ($50.75)
UTG ($59.30)
MP ($56.20)
CO ($23.50)

Preflop: Hero is BB with Ahttp://www.flopturnriver.com/phpBB2/...iles/heart.gif, 7http://www.flopturnriver.com/phpBB2/...iles/heart.gif.
4 folds, SB raises to $2, Hero calls $1.50.

Flop: ($4) Thttp://www.flopturnriver.com/phpBB2/...miles/club.gif, Ahttp://www.flopturnriver.com/phpBB2/...iles/spade.gif, 7http://www.flopturnriver.com/phpBB2/...miles/club.gif (2 players)
SB bets $4, Hero raises to $12, SB calls $8.

Turn: ($28) 5http://www.flopturnriver.com/phpBB2/...miles/club.gif (2 players)
SB checks, Hero checks.

River: ($28) 3http://www.flopturnriver.com/phpBB2/...iles/spade.gif (2 players)
SB checks, Hero bets $12, SB calls $12.

Final Pot: $52

Pretty apparant that I had the best hand. But what is the best line here? I feel as if sometimes he'll push the Acxx and I would be very hard pressed to call a c/r. Also if he doesn't have the Ac, his hand cannot stand much heat at all and my raise on the flop can easily be a big flush draw/98/set/2p and most of these things now beat him and he won't be able to call a turn and river bet anyways. Was this the best way to max value? Would this be better if the Ace were a club and the ten were a spade?

There's not much more value to get I think. You'll never win much when villain doesn't have much.

River maybe 16, but that's already >1/2 pot, so you played it fine imo.