Simply clicking on a planet would allow one to see what ships were being built and their time frames.
I never had problems with not knowing what was being built while playing the largest maps. Most the planets were fairly generic, I would place everything (usually) as soon as I colonized a planet. The special projects and wonders I placed personally so knew where they were and their times of completion.
If I ever got lost I simply used the planet list which describes everything in an easy-to-use interface.
Eventually I would be completely expanded out with the map (the "Strategic View) and would have to zoom in on particular planets just to see whatever symbols are on 'em. Would take less time to just click and see the planet itself.
I could see, maybe, a hover icon that could pop up after a few seconds. But, to my mind, that would just be the same thing as clickin' and would even take more time.
'Less I'm completely misunderstanding something.