I found this website the other day...
Atomic Rockets
Also referenced is this site...
The Tough Guide to the Galaxy
Also this chart seems very appropriate to SEIV and probably SE V ship building...
Weapon vs Propulsion vs Defenses Chart
Also the weapons section has some very interesting stuff as well...a good if not long and very scientific read at times...but I believe some modder out there might find some inspiration....
Kana