Yes, all of these problems can be summed up as a single phrase: attention span. The AI has no attention span, no memory of what is happening from turn to turn. If a ship hits a minefield, it doesn't REMEMBER this and build a mine sweeper, it just sends more ships. If a colony ship gets destroyed trying to reach a world that the colonization minister thinks needs to be colonized it just builds and sends another and doesn't even bother to send an escort with it. If you wipe out all the planets it held in a system it doesn't remember this and attack your fleets that have just wiped out its worlds with many millions of colonists... it suddenly decides that the fleet that was guarding those worlds needs to be someplace else guarding something important.
Somehow this AI needs some continuity in its actions, some DEPTH of planning and reaction.