.5/1- tough AK river spot.

[Micro2Macro]

Your reasoning for not betting the turn larger is flawed. If he's going to call a larger bet with all his weaker hands it will be more profitable to bet larger.

Also on the flop betting larger ($5+) seems best because he's going to peel just as light if you bet larger, therefore you get more value.

On the river, you need to be good 16.75/(16.75+33.50) = .33 or 33% of the time at least to break even on a call. Given your read that he's fairly splashy I think it's reasonable to assume he will lead the river with Ax and missed draws along with Jx, so now your job is just to put him on a range for leading, run it through stove and see where you stand. It's probably a good idea to try a few different ranges to give you a better feel for this spot in general.

[Stacks]

On the river, you need to be good 16.75/(16.75+33.50) = .33 or 33% of the time at least to break even on a call.

You actually only need to be ahead 25% of the time [(16.75) / (16.75 + 50.25)]. I agree though that flop/turn should be larger, and river is a call.