Hey trollord59,
GTO is a bit range vs. range. So in theory, if you are UTG and openraise, the whole table has to prevent you openraise a hand like 98s +EV. Every position has to 3bet a a certain frequency. Nobody knows the correct frequency for every position and it depends on your sizing also. But all positions together should 3bet around 30% and call some hands to make your weakest holdings indifferent raising or folding (thats why nitty tables with one fish are very profitable, they fold to much and you can openraise way more from UTG).
Now there are some oldschool-strategies at the tables with flatting more than 3betting in MP and CO vs. UTG and 3betting more on the BU and SB or more "new-school" with nearly 3bet only MP vs UTG and SB vs UTG.
There is no really preflop-equilibrium out there because Holdem multiplayer games are not solvable yet (good for us). I think Pokersnowie has the best approximation to GTO nowadays.
Okay, GTO is not about balancing it's about maximum EV play range vs. range, balancing is a byproduct and there are some spots where you cannot balance because it isn't maxEV. In some rare spots all bluffs range vs. range are -EV and in theory you have to call only but thats not GTO
or rather maxEV because we have a problem with AA than. If you take the passive line with AA you lose much money in the long run with that hand because villain realizes equity (you are not losing with AA obv but the EV(aggressive line; AA) >>>>>>>> EV(passive line/call;AA). But thats should only be an example.
If you really want to construct a "GTO"-Range UTG vs. x you have to take the weakest 3bet-range in villains bluffrange and make it indifferent, with all other factors ---> cold4bet-percantage, rake etc. With some knowledge you can construct your own "GTO-Strategy". After that you'll need a program like Cardrunners EV to check the EV (it's not mandatory for that spot imo)
It's not easy and coaching-stuff to be honest but it is no big moneyspot where you gain a huge edge. You just have to be clear: OOP you should 4bet a bit more because calling becomes a bad option. IP you should 4bet fewer hands and call a lot to realize more equity with your whole range (keep in mind, villain realize equity with his 3bet bluffs also in that spots, to make his weakest hands indifferent with the "call-approach" you have to call a lot and fold ~35% but it's often maxEV playing that way IP).
Okay, that was for trollord59 because he'd wait a whole month for a response from me^^
Now your range UTG vs. MP: like I said, it really depends on villains approach, his sizing and your sizing.
If you raise 3bb and villain 3bets 9bb, your odds are okay and your range is good. I see no reason to bluff, just 4bet AA KK and AKs (your semibluff) and call some good stuff, like 77+, AKo, ATs+ and some hands which perform "okay" against bluffs and valuerange, like QJs or JTs. Believe me, nobody exploit that and if he writes in the chat "lol, AA, KK, AK, easy snapfold", no problem because he often get good odds against 4bet and make the incorrect fold and thats good for your range OOP.