When I need to start upgrading mex T2, and when to finish them?
When to go for T3 mex? T2 power? T2 factories? Commander upgrades?
When can I expect first nuke? and so on
we do not really have that, cause maps are different you always have different amount of recources, and cause maps are pretty open you can't usually just build a "bunker", but also on SupCom it is easyer to expand all over the map, so usually does not matter what you do, sitting on base will be super bad
when to expect nuke? well some one could test witch is fastest possible nuke on some maps, but it is like alsking "when i expext my zerg opponent to be at 200 supply in SC2, if you do not attack it can be around like 8-10 mins, if you attack it can be delayed to infinity, or delay of any degree depend on your agression and enemy skill and greed
you barely have any timings here also casue speed of building depend of amount of recourses and amount of assisting engyneers
only timing i use is 1:17, time when normal "First bomber" can be build, but even with this tactic you can do it faster, or delay it in any way you want
there are also some simple bilds like "second air" "3rd air" or any kind of build focused on making factories, and all those builds can be boosted by no making defencive tanks early on and skipping mass extractors/pgens and useing reclaim instead, it will boost your build but hurt eco in long term (usually)
on seton's 4v4 you have timing when ACU comes to mid, timing when usually people start RAS and both of thouse timings can be delayed if player decides to make more mex upgraide or just build other units...
on rush me more 4v4 there is t3 bomber timming: timing when everyone has to have shields on main mexes cause map is stupid and you have all mexes in one place clumped up, and people rush fastest possible t3 bomber and kill 8 t2 mexes +storages in one pass and do same to other players without even stopping bomber
if your opponent uses same build over and over again, you will be able to use his timings against him
and actually there are timings when you would expect people to send engyneers somewhere, so you can send you raiding unit no to early, but for me it more depend on feeling and it also ofc depend on enemy build
also on theta passage, when you play against cybran they can build fast jester and you might want to scout what is his second factory, and you will need to know timing for that, but you can also just look at your base, and right after you and your enemy finish hydro you would like to scout with a land scout, that will be a big deal for cybran, sometimes i even go for radar before second fac to deny scouting, or hide second fac not matter what you choose land or air, that will cause tons of paranoya, and may force air factory from your opponent so he can scout you
when you should build t2 mex? if you are not want to finish your opponent fast with some super agression you need to eco, ususally best way for early eco is to expand(t1 mexes) and make power and make engyneers, then t2 mexes, then make storages around them, then t3 mexes and whatever... When do you start them??? as fast as you can efford without dieing... that is answer. there is also one rule: you want to be ahead in eco, but need to be 100% sure what your opponent doing then you can do whatever you want, but if you do not know what is enemy doing, you might want to spend some recources on scouting and defending and building units, and also you need to be ahead in eco to win, there are not much diffference in haveing 2x more eco or 5x more eco than opponent, but if you invested in eco so much that you have 5x more you probably will lack defence and can die to some drops/bomber snipe