As ohartenstein23 said in the first response, you can change the repair rate in a mod. My mod does this, as I feel that it doesn't make sense that it takes so long. When I wrote my mod, I wasn't comparing build time to repair time though, I was instead thinking that a higher hit point craft isn't just more metal to damage, rather it is a tougher ship that actually takes less damage per hit. That is why I think the alien alloy craft should repair much faster.
But also ignoring realism and thinking only in terms of gameplay, a brawler needs three things to really be better than an interceptor:
1.) more speed, so it can catch things the interceptor can't
2.) more hit points, so it can survive in fights the interceptor can't
3.) faster repair, so that it can get back in the air sooner
If it lacks any one of these things, then it severely inhibits the craft's ability to truly stand above the interceptor as a brawler. But I guess in Vanilla there weren't any brawlers. All those hit points were largely useless save for the occasional mistake or that one time you just decided to pit everything against a battleship. Everything else could be easily outranged with plasma beams and avalanches, and the supply ship was the only one with enough hit points to warrant using something bigger than avalanche missiles. You could cheese down a terror ship with 2 interceptors and start-game tech, only hard part was catching it.