I think it would be helpful if you shared the parameters you used for the simulation. Starting ranges might be a little unwieldy, but what bet sizes did you allow on each street, what size raises, etc? Among other things, this will probably be a helpful thing for me to give you feedback on 😉

The trouble you’re going to run into there is that even if your opponent used a particular sizing on the turn or river in this hand, that doesn’t mean he wouldn’t have used other sizes with other hands. Denying him those opportunities further down the game tree is going to influence his ranges on early streets. Like, if he can’t overbet shove river, that’s going to reduce the profitability of certain flop check-raises.

Allowing multiple options on early streets explodes the game tree and can make simulations really cumbersome, but on later streets it’s easier to do. At the very least you should include the “all in” option on the river, for both players. Ideally allow a small and large size on the turn, and small/large/all in on river.

Also ideally, there should be something you’re trying to learn from a particular sim other than just “Did I play this hand OK?” and that should determine the sizes you allow. Like, you were unsure about whether you should have bluffed the turn, then it’s particularly important to include multiple sizes for turn bet so that you can be sure there wasn’t any size where it would have been good.

Make the sizes pretty different from each other. Allowing both a 50% and 60% pot bet isn’t going to do much. You want stuff like 33% and 100%. You’ll get a feel for this over time, but a hint that you’ve chosen good sizings is that there are certain hands with a clear preference for one size or the other, even if some hands split between them. If every hand splits between them, there’s probably an optimal size somewhere in between.

The all-in on the river is a convenient way of making sure your opponent has some way of getting all the money in. Of course there are times when it will matter how the money goes in, but less so than you might think. The river overbet will compensate for the fact that your opponent might choose to use a larger bet size than you allowed if you check behind the flop or something. It just ensures that no matter what line you take, he can always apply max pressure eventually. If you don’t allow that, then you can get some weird results like less slowplaying if he has no way of getting all the money in without raising the flop.

If you’re confident that you can predict what sizes your opponents will use, then go for it, but when in doubt, always make it possible for them to apply max pressure on the river.