First 2 orbits of session

Hero raise AdJh to 3bb UTG 6-Max
CO Calls 3bb and has 100BB

HU to flop
JdKc2s
Hero Checks
CO bets $3.75
Hero Calls

Turn Ah
Pot = $14.50

Hero Checks
CO Bets $5
Hero calls

River Ac
Pot = $24
Hero Checks
CO bets $20
Hero goes All-In for $81.65

Against an unkown, is this C/Jam too thin, or just fine?

There are no A2s Combos left for villain, and I assume villain 3Bets AK at some frequency, leaving him with less than 3 potential combos. If villain folds 22 or doesnt call preflop(think 22 mostly is flatted here however), then we are banking on him calling with JJ, another hand which he may 3bet pre or be able to fold on river. There is also QTs which will take this line, but again, should certainly fold to a jam.

Against a player I know to be a reg, I imagine C/jamming here is too thin because we really aren't being called by worse, but against an unknown, are we simply giving up too much by not going for thin here for the times we are up against a weak player who will have a hard time folding an absolute strength strong hand?