Halo had amazing story, Halo 2 had amazing Multiplayer, Halo 3 had amazing custom games, Halo Reach had amazing Forge, and Halo 4 has a little bit of all of these. I own, and have beaten all of these multiple times, and I love them all dearly. Sure you may have the issue of joining in late, but I distinctly remember the ****-storm that surrounded people not being able to join mid-game in the first place. As well as this my go to load-out is
Storm Rifle
Boltshot
Plasma Grenades
Shields
Reload Time
I rock it as MVP in about 75% of Slayer games, and I'm rank 25. So, If you don't like 343i's 'first' legitimate game, don't play it.