Hit markers help provide feedback in latency-rich games, dropped shots in H3 were annoying. There's nothing wrong with them being added to guns, it's just confirmation the shots are going where you are aiming. Hit markers from grenades and similar situations should not happen, though. You shouldn't be able to probe with grenades.
I let my xbl gold run out 2 weeks ago for the first time since getting a 360. Halo has always been able to keep me interested, but not anymore. It's strange, I thought reach was bad but was able to stick with it for 2 years; I couldn't even go 8 months with halo 4.