Galus makes a note in the OAV that the Alliance and the Bugrom will destroy each other; "Who says history can't repeat itself?" Unless, of course, this is assumed to be an entirely seperate story within itself, but at least Ifurita's memory seems to cotain insectoid-ish looking warships...
As for Jinnai, that was a very interesting bit of insight about his overloaded senses, something I had never even thought about. The only thing I ever speculated was that his ability to communicate had to at least be on some mental wavelength, or better yet, the "radio" communication you had noted.
The writing was great in a general format, but in detail, the Groucho one seems way overdone. It's like glorified text, perhaps what he thinks, but I doubt it's something he'd be able to "say".
I figured he had to have some telekinetic ability, but I never thought of him inheriting traits that are closely related to a bug
and some factor must've prevented the humans from becoming scientifically advanced again, though that could be just about anything.