It might be worth noting the Star Fleet adaptation for Starmada.
The original versions of Klingon Armada (and other books published to this point) had been based on the Admiralty Edition of the Starmada game system; while a new set of revised books are in the process of being done up in order to support Majestic 12's latest Nova Edition instead.
In terms of complexity, Nova seems to be more streamlined than Admiralty was; but even the latter edition was quite different to what one might have expected to see in SFB and FC.
Also, do you want to stick with the starship combat game engines only?
ADB have a few other scales of action; from the recently-released Star Fleet Marines: Assault covering battalion-level ground combat, to the grand strategic level offered in Federation and Empire.
However, if you wanted to stick with the games intended to work with the Starline 2500 minis, they might be overkill; unless you are planning on getting an immense scale version of the F&E map, and are crazy enough to want to try and use your minis in lieu of counters...