Following the changes to the AI in patch 3.3, the developers deem it safe to move on to other aspects of the AI, aside from the economy, in patch 3.4 and focus on the military.
The changes coming to military fleet behavior in 3.4 are mostly bug fixes rather than improvements on their decision making, so while there should be a very noticeable difference, the work made so far on the fleet behavior will not be as encompassing as the work made for the economy, the developers point out.
While there were issues where AI would split their fleets too much, fundamentally this behavior of AI splitting fleets was by design. The AI would allocate just enough fleet power to their objective in order to carry out as many objectives as possible.
The main issue came from the amount of low fleet power targets such as unupgraded starbases which caused the AI to frequently split their fleets into 1000 fleet power pieces.
While in theory, this approach is quite good, the main two main issues with this approach are that the player can easily just take one of their bigger fleets to go around and defeat the AI’s smaller fleets one by one which makes the AI somewhat incompetent, as well as that this playstyle from the AI can be quite frustrating to play against.
In 3.4 the AI will aim to have full fleets as their smallest unit to carry out military objectives, AI will actively try and merge all possible fleets during peacetime and the AI will during a war try and merge two nearby fleets when possible.