thanks for the reply:)

When would I go all in? When it is shown that SB does not slowplay his hands. If he barely ever shows up with Tx or better.

Hmm I do think that this might be often true at these stakes. Which is kinda tricky, because otherwise we would be clearly opting for a smaller sizing (maybe sth around 1/4?). However, I am strongly convinced that we will hardly ever see here a Tx.
Lets assume that we have 50% FE when jammed, so he needs to have less than 25% slowplayed Tx or better, in case we are betting for value. Personally I wouldnt be concerned about this fact.

My main concern is that he might start overfolding and therefore we would be isolating ourselves.. you know then he needs to have like 10-20% of slowplayed hands which dominate us. Maybe its still ok(ish)

Btw by betting smaller, do we always bet/fold? As you mentioned, a decent portion of his range are just bluffs, so that there is some probability that he might just start putting us on overpairs with intention to represent Tx or FH..

I created a Google Spreadsheet to give you an idea on how their slowplay % and our sizing work.
The formula at the 4th column of a table =(((100-E2)A2)+((E2-D2)(A2+C2))-(C2*D2))/100

Times they fold + times they call and we win pot + out betsize - times they have slowplayed and we lose our bet.

As you can see the lower we go the more profit we would be making in theory. This is because their slowplay% is a set number in those tables. And the smaller we go the more profit we are turning because we beat all the other hands that are now forced to call.

In reality though, SB is not going to call that often. So you would need to look at the MDF mainly. How often can SB call us? Going below that sizing from that point would be losing EV. I have simulated this in the first table. You can compare Column F and G and notice that as soon as your betsize makes SB's MDF go over 0.7 you are starting to lose EV by going a smaller betsize.

So when you think your opponent isn't going to call very often (< 50%) then go for the big size. If you think he will be calling very often (> 70%) go for 1/3th size would be my simplification.

This doesn't keep in mind the few times we ourselves have a monster and SB jams on us with worse and we call it off.

I could see that being profitable, probably in theory one of the worst PPs to be doing that with, since AA doesnt need the protection as much as other PPs do. Id argue its a somewhat big variance play, since people are pretty honest here and on the next streets, so we could navigate it smoothly.

downflux01 would you fold on later streets unless improved? If yes, I don't see the merits of calling the flop raise.

crazyriver If im facing too much action, yes, because I dont think Tx is going to overplay like that too often.. but my assumption is that most of his (semi)-bluffs are not going to shove as a bluff OTR to frequently, so I dont have a tough decision if I have to fold. Shove OTF seems a bit risky, a fold too nitty yet - so Id prefer the middle of both and call

downflux01 my only problem here is that we have SPR < 1, once we call the flop, so it feels like we have to make the decision at this point whether we're calling it down on later streets or folding. I simply don't see a scenario, where I would call flop and give up on later streets that "shallow". But I might be totally wrong, as well...