You really don't see that many [GC] GBs as you think. You just notice more when they are there, and don't remember the fights as often when there isn't a cap. I'm more likely to remember a vs Cap battle than a vs VHF/B battle. Its just normal. Anyway, GC has a total of 2 gunboats. Any others you see are indies. I don't think they have any cruisers.
And the Red Cats. Well thats more by necessity than choice to be honest. Being in Kusari, in Hokkaido in fact, is right smack in the middle of the niobium-diamond route. As such, when we pirate traders, there are numerous BHG BCs and BSs that come for us. So there is a higher demand on bombers than there are fighters, as we fought, on average, 80% capships, 20% fighters. Possibly even lower fighter percentage than that.
And the Red Cat cannot outturn a fighter. I've fought both the Kusari Cat and the Red Cat, and can outturn both in a Stinger and a BD HF. Chimaera is better in agility than a stinger, and just slightly less in agility than BD HF (Due to hull points being ~3,000 points higher), so it can outturn a Red Cat as well. If our enemy brought in all Chims, and we brought in Red Cats, we would stand a good chance at losing. It is simply dependent on whether out opponents have trained thoroughly in anti-bomber fighting. If people want GC to use less bombers, than bring in more fighters.. But if you keep using capships, GC are going to keep using bombers to counter them.
I try my best to find out the ship my opponents are flying before getting in combat with them, so that I may bring a ship more appropriate to the fight. I don't want to bring in a Red Cat vs a bunch of Chims. I'd rather bring my HF, for RP and PvP reasons both. This morning was an example. A KNF was fighting a GC bomber. Another GC went to assist in her bombers. I found out halfway to the fight that the target was a Chimaera, turned around, flew back 15km just to switch out to an HF. I wasted 2 minutes, in which time the GC bomber may have died, so I could bring an appropriate ship. I ended up doing most of the hull damage the Chim had recieved before getting SNd by the bomber, (By the bomber who had no weapons except SN.. I inferno, she SNd, I blinked.. Lolwhat? O.o) simply because I was able to turn more effectively. I had the trouble of having to conserve energy to fire, but when I did fire I did so much more accurately than the other GC bomber present.
(BTW, I am not in the GC player faction. I am speaking here in general for the GC population, myself being an indie GC as my Kiretsu characters.)