AA line check. 2-4, 3 flush board

[JooWish622]

Hand prior to this Villian bet the flop of 832 and I folded after raising preflop.

Hero is dealt AA in CO. 6-handed. VIllian is in BB, no reads, sat down an orbit ago.

Folds to Hero who raises to 15 with red AA. Folds to Villian who calls. Hero has 1000 behind and Villian has 400.

(pot 36). FLop is 8d 3d 5d. Villian bets out 10. Hero Calls.
Turn: 2c. Villian bets 40. Hero Calls.

River: As. Villian bets 10. Hero raises to 100, Villian Calls.

What are the advantages of playing this as passively as possible until the river. Part of the reason why I chose to was because I had a suspicion that Villian may have flopped a big hand and I would not want to overvalue my AA and flush draw with stacks deep.

What would you have done if turn was a black K?

I was intending on calling down from the flop, unless the 8 paired and he fired.

Results to come.