iPoker, Hold'em No Limit - €0.50/€1.00 - 6 players

UTG: €164.45 (164 bb)
MP: €141.88 (142 bb)
CO: €181.60 (182 bb)
BU (Hero): €136.55 (137 bb)
SB: €106.00 (106 bb)
BB: €87.20 (87 bb)

Pre-Flop: (€1.50) Hero is BTN with A♠ K♠
3 players fold, Hero raises to €2.50, 1 fold, BB 3-bets to €10, Hero 4-bets to €22.50, BB calls €12.50

Flop: (€45.50) 9♦ 6♣ 3♦ (2 players)
BB checks, Hero checks

Turn: (€45.50) 5♠ (2 players)
BB checks, Hero checks

River: (€45.50) A♥ (2 players)
BB bets €64.70 (all-in), Hero?

villain is a nitty semi-rec: 20/7/7/h:100

Most of my turn checkbacks are AJo, AQo type hands without diamonds and clubs, AKs, AQs, A5s, A3s, some JJ+ with a club and occasionally (not too much) flush draws and bricked backdoor flushdraws like KJs, JTs, QJs. All in all, I have more aces than him on that river. Because of my range, I don't think jamming from the big blind is a great line in this specific case. Moreover, IMO this line is very unbalanced and very value heavy, trying to stack off as much Ax as he can, avoiding checking behind middling hands.

What value hands can he have here?
4 combos of 78s
2 combos of 56s
12 combos of sets
2 combos of A5s
1 combo of A3s
21 combos of value hands

With this sizing, he should balance his jam with 8 combos of bluffs and if this is the case, I should call with ~40% of my river range. BUT I dont think this line will EVER contain 8 combos of bluffs, am I right? So what hands do we call then? Of course, every A3s, A5s, AA, and? We can fold every AQs and AQo, AJs and AQo, every slowplayed big pocket pairs, but what about AK? How much do we have to overfold here, what do you think?