Start sniping... There's also shotguns and secondaries.
To the OP: Yes, prestige on weapons resets your attachments, but you also get to collect that xp for unlocking them again. I just wish it was 3 prestiges instead of 2, but I am probably in the minority on that one. You should also aim to get the "Camo Challenges" done. The camos won't reset when you prestige, but they can give a lot of xp for leveling your character. So, even if you don't plan on getting Diamond, you should plan on doing the challenges on the weapons you like anyway... Unless you don't plan on prestiging your character.
There's no REAL point in doing it if you aren't going to put the xp to work in some way.