Cbet bottom of range or not?

Hand
PokerStars Hand #128600157074 begins at 2015/01/13  3:15 pm
Seat 1 (Mr Pkface) is the dealer
B4RT90 posts the small blind 0.10
ivannnntw posts the big blind 0.25
DianaSvensk raises to 0.75
pinkiBlinki folds
Andriyko1982 folds
Mr Pkface folds
B4RT90 calls 0.65
ivannnntw folds
Flop: [7s 5h 6c]
B4RT90 checks
DianaSvensk checks
Turn: [3c]
B4RT90 bets 1.50
DianaSvensk calls 1.50
River: [Ks]
B4RT90 bets 3.50
DianaSvensk calls 3.50
Action has ended

[P] 

33+,A2s+,KTs+,QTs+,JTs,T9s,98s,87s,AJo+,KQo = 15,38% = 204 combos

Cbet v: 
55 (3), 89s (4), 66 (3) = 10
TT-KK = 24

Tot value bets: 34

Cbet B: 
A9s (4), A8s (4), 9Ts (4), 44 (6), 33 (6) = 24
Backdoor fd: TJs (3), TQs (3), TKs (3), QJs (3), QKs (3), KJs (3) = 18
A2s-A4s (9)AT-AKs (12) = 21

Tot 63 bluffs


Strong check backs: 77 (3), AA (6), 88 (6), 78s (3), 99 (6)

Tot combos Cbet: 107 (52% combos cbet)

Ie, I don't think checking back 33 was a big mistake, but we could also put it in the bottom of our "cbet bluff 1-2 streets" category.

As played, villain shouldn't have many 4s in their range after calling sb vs utg (most players folds 44) so when he/she is betting twice here I guess he's repping an over pair or betterz and is expcing to never get raised, since I shouldn't have any fours either.

Because of that, it would be an interesting question wether we should/can value raise a set on this board. At least KK should probably be a river raise.