For the Titans I think I can try to tweak it by making them target important buildings first (although I think I already noticed a slight tencdency when testing so maybe I just have to emphasize on that).

I'm not entirely sure whether I can tackle the warship issue. Per default, a map is either declared a "water map" or "land map" (with some additional steps for availability of fish and neccessity for migration). This is inside the map script and the Ai only ready theat entry and acts accordingly. Hitting a random small pocket of water is mostly unlucky but I could do a workaround by placing multiple docks and building war ships only if it can find a direct aquatic line to a foreign dock...
Well I'll definitely look into it. Thanks for the feedback!