I will start by saying that as they stand now, strike craft are great. I read that they are being rebalanced currently, and I think the Sabres, Longswords, and Seraphs themselves are really cool. I also read that a Flood strike craft model has been completed. Now the UNSC launches Pelicans for bombardments and the Covenant may use Phantom gunships in some fashion. Good stuff.
I had an idea though, which was inspired by SoGE. In the Star Wars mod every faction has a "Advanced Starfighter Designs" research that allows carriers to launch a new type of fighter and bomber in addition to the original fighter and bomber. For example, the Rebels start out with X-Wings and Y-Wings but can later build A-Wings and B-Wings in addition to the XY-Wings. The catch is that the original strike craft, though lower performance, can regenerate faster. My idea is that because this mod is built with the war's evolution in mind (the future addition of Stridents, the evolution of Halcyons, etc.) perhaps some evolution could be added for strike craft. So here goes:
UNSC
Early game Fighter/Bombers: Longsword interceptor and Shortsword bomber
Late game Fighter/Bomber: Broadsword fighter and Pelican gunship
Planetary Defense: Sabre
Covenant
Early game Fighter/Bomber: Space Banshee (or possibly Tarasque fighter) and Gigas bomber
Late game Fighter/Bomber: Seraph fighter and Phantom gunship
Or some variation of that. I think that if the craft are differentiated it will make battles look even cooler and give players more options when arming a fleet.