1) The AI appears to know exactly where the habitable planets are located.  I could see this being a fine perk for the AI on the hardest of difficulty settings, but it seems at bit unfair on the lower settings. This may not can be fixed right away because currently the "Explore" algorithm seems to just search for empty space, not for nearby stars that haven't been explored. So perhaps some work into a new "Explore - Stars" algorithm is needed. 

2) In previous patches the AI had Constructors just sitting around all over the place doing nothing.  Maybe this has largely been fixed already. But for higher difficulties, the AI should know how to create 5 starbase formations(or at least 4, since 4 would be much easier to code) around a single planet for Economic starbase usage or for Culture starbase beacons(on certain factions).  I know some work has been done on AI Constructor preferences, but I feel this area can continue to be improved much further.

3) ***The AI desperately needs make better use of building space on planets.*** The initial space should be filled with T1 buildings before upgrades are considered. Upgrades are a pretty inefficient use of resources in general. AI should prefer terraforming, before upgrading T1 buildings when possible.  AI should invest in Terraforming techs much earlier as well.

Getting AI to properly use adjacency bonus seems a harder task, but perhaps start with small improvements.  Such as if there's a 3 hexagon triangle available upon planet foundation, it builds its 3 factories there(so they all get +2 adjacency bonuses.

4) AI should be coded to go to 100% Manufacturing for at least the first 10 turns after planet foundation. This is the efficient course of action 99.9% of the time upon planet foundation. i guess this one may largely be effected by the "AI governors" and wether they make it in before launch.  In general, all AI planets need a governor that heavily emphasizes either Manufacturing or Science. Income governors should only be triggered if net income for faction goes below 0(At least with games current economic state).

5) AI should charge heavily restrictive prices for purchase of Military ships through diplomacy. Perhaps also charge a higher price for Military tech trading as well. Factions shouldn't be very willing to trade anything military related.

6) Player should have more warnings to give the AI before outright declaring WAR.  If computer doesn't comply with reasonable request, then they shouldn't hold a grudge against the player forever because of a WAR caused by their own aggressive actions.

Basically, the player can't make many of the request that the AI can make of us.  The request should be able to go both ways.

Minor races are building starbases way far away from their home planet, and stealing a lot of the available resources.  I'm talking about halfway across an Immense map here.  They also seem to know where those resources are without having to explore first.

Unfortunately i cant provide a save as i have reformatted recently 

i noticed that the ai seems to either ignore range limits or has an unlisted 100% bonus to range 

i was playing an immense map * i changed ship range in mapsizes  globalcombatmods to -0.20* 

i had an AI freighter reach one of my planets  the planet was at least 80 tiles away from the nearest ai planet/starbase and after checking the freighters specs and race mods / teh mods  determined that  the ship should have had ~ 40 range 

i went and looked for everything including resources techs racial abilitys and even looked what kind of bonus's the ai got on different difficulty levels even if i made a couple of mistakes my estimate was ~40 range it should have had and ~ 80 was the distance it was traveling. if it was 45 or 50 i could go hrmm maybe i missed something but this was at least double its range.

and with the minors also seeming to ignore range as others have said i wouldnt be surprised to find that range does not work for the AI

   1)  AI does not terraform.  Altaria was still a class 10 when I found it around turn 100

   2)  AI, both minor and major, build way to many mining bases before they build economic bases, or colony ships.  Most strategic resources are kinda useless early on, and should have a lower priority than building colony ships and economic bases.  Minors and Majors grab every location on the map with 2+ resources in range of a single starbase in the early game.

   3)  Minors should not harvest relics.

   4)  Minors should research soldiering and defense techs.

   5)  Minors know where all resources are and their constructors have infinite range.

   6)  Minors rarely build defensive ships.

   7)  AI rarely researches universal translator, and does not trade with minors even when that tech is traded to them.

   8)  Drengin (and others) often research Extreme Colonization before basic weapon / defense techs.

   9)  Minors are usually broke once they run through their starting cash - starbases are expensive.

   10)  Minors rarely research trade techs or build freighters.

   11)  Auto designed support ships rarely have a second engines.  6 support modules and a sensor bay, but only 1 engine.  I use 2 support : 1 engine in my custom designs.

I have played several games where all the available planets get taken right away on small maps.  This happens even when I make trades to obtain other AI's survey ships.  Even with 3 - 4 survey ships at my disposal + the ones I obtain from surveying anomalies, I am finding settled worlds.

Also the AI REALLLY undervalues resources. Often trading them for a low level tech or some cash. 

As a player, if you are willing to dump some tech to the AI, grabbing all the resources (nanites, hyperstones, etc) can give you a massive lead. Individually they aren't great, but buying every single one off every single AI gives you a huge advantage.

Nothing like having ships with +100% capacity compared to the AI Bet they regret trading me all their Helios Ore for a few age of expansion techs now!!!