I'm hearing the economy is tighter and resources matter allowing for actual strategy and the A.I has some idea how to play the game? Is it finally gold and reached potencial? I was waiting for this stage before I played big.

It's definitely a lot better than at initial release, but...

Trade routes are still broken good and you can easily hit 999+ luxuries / turn or drown in Dust due to their exponential growth, and they're actually next in line for balance. Hero EXP is getting changes as well, because in the current state governor heroes rack ridiculous amounts of EXP whereas admirals get almost nothing in comparison even if they're constantly fighting and sieging. Beam weapons are also supposedly receiving a much needed buff. As for new content, Amplitude confirmed they're releasing fighters and bombers, which were originally promised for release but cut due to time constraints, by the end of summer as free content and if you're lucky the game might have a sale by then. 

The endgame Academy quest also clearly has placeholder in-game rewards that have no influence on the rest of the universe (last I played the rewards were much more tiny than anyone's per turn resource income by that point in the game) and the devs have mentioned they're going to overhaul it in some way in the future, though I don't think they've announced anything concrete as of yet nor if it's going to be free content like strike craft or future paid DLC.  It also triggers so late in the game that most of the time the match has already ended in any victory condition. Point being that if you were drawn in by the kickass Pathfinder trailer and hopes of epic story or finale I wouldn't keep expectations very high for its current state.

AI can now design and use fleets much better, but I think they're still quite a bit lackluster in diplomacy department and it's very easy to stay friendly with them using only minor bribes since they don't really seem to care about the player nearing non-militaristic victory conditions. In war as well the AI seems to heavily overvalue luxury and strategic resources even if its fleets greatly outnumber yours and will usually accept a tiny tribute at the first turn of war to end it, so unless you're playing Cravers or Vodyani who specifically thrive on war you're pretty much never forced to go down the military path with other factions as long as you remember to hoard resources other than Dust for bribes. The AI doesn't really manage its systems as well as a player can either, and I think I've never been forced to attack AI myself in order to stall their slowly nearing Science / Wonder / Economic victory. As a result Endless difficulty is still bit of a cakewalk, and I'm by no means an expert 4X player. 

There's been changes to AI in every patch IIRC (including making them more prone to seek victory, at least on paper) but I don't remember the devs mentioning when and if they're fixing the above mentioned issues. However there's supposedly an AI modding beta, but I'm not sure how quickly they're going to start overhauling AI diplomacy. 

tl;dr

Anyways if you already decided to wait for the game to reach its proper full potential first I'd suggest waiting a bit more longer at least.

At least for me the only thing stopping me from playing it is crashes and random game breaking bugs after turn 100. Some of the quests seem imbalanced in my opinon too (travel to the other side of the galaxy after turn 8 etc) I too am waiting for the fighters and bombers and some improvements to the battle camera.