25NL Top set, raise river?

[UFGatorGuy]

No reads on villain, this is his first orbit. I c-bet this flop 90% of the time, however, I'm trying to experiment with this. I know you need to bet with sets, but when it's a board like this, I feel like you see a fold over 90% of the time. With 66 on an A63 board, you get paid off by most aces. KK on a K78 board, I think that in most situations only the case king would call and he most likely doesn't have it. It is a drawy board, though, so in hindsight, I think I should have bet the flop anyway. If the flop came down K72, would you guys be in favor of checking behind?

As for the river, do you give a random villain credit for having hit his draw? Is this a call or a raise? Comments on all streets appreciated, as always.

PokerStars No-Limit Hold'em, $0.25 BB (6 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

SB ($24.75)
BB ($167.65)
UTG ($32.10)
MP ($23.30)
Hero ($26.30)
Button ($12.85)

Preflop: Hero is CO with K[img]/images/graemlins/club.gif[/img], K[img]/images/graemlins/diamond.gif[/img].
<font color="#666666">2 folds</font>, <font color="#CC3333">Hero raises to $1</font>, <font color="#666666">1 fold</font>, SB calls $0.90, <font color="#666666">1 fold</font>.

Flop: ($2.25) K[img]/images/graemlins/spade.gif[/img], 7[img]/images/graemlins/club.gif[/img], 8[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
SB checks, Hero checks.

Turn: ($2.25) 9[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">SB bets $1</font>, <font color="#CC3333">Hero raises to $3</font>, SB calls $2.

River: ($8.25) 4[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">SB bets $3</font>, Hero ???