I started playing Halo in 2009, but with Halo:CE and 2 (one right after the other) on the original Xbox I was borrowing. I fell in love with the game just from the fun campaigns and universe surrounding the games. I then went to Halo 3 and got Xbox live. When I started playing, I knew it was going to be fun. I loved Halo 3 MP, but after a few years it's still fun, but too slow for me.
I went on to Reach, and it was great in my eyes. I played the hell out of it's MP, for over 40 days. I'm two ranks away from max rank in that game. After that, It was Halo 4 time. I loved the campaign. I was in awe from the moment it began and was very impressed. The MP was fun, (It seems Halo has that running theme) but it was too short in my opinion. That was about my biggest gripe with the game is that I just leveled up too fast.
I'm okay with what Halo 5 has to offer. This game seems like it's a true evolution of Halo MP. They brought back loved elements of the early Halo MP: such as De Scope, Weapons on map, Fair starts, what appears to be a longed for ranking system... added things from the later releases and fixed them or took them out because they didn't work: Sprint with it's penalty, Loadouts, ordinance... and wrapped it around new features that a Spartan should be able to do. They took the best of classic and new, and meshed them together into something that appears (so far) to work. I for one am a person that gets Halo mostly for it's Campaign, so I would've probably got the game no matter how the MP turned out, but that does not mean I am not critical of it. The gist I see: Bring back good stuff, get rid of bad stuff, added cool new things. It is a true Evolution, while sticking with a working formula of past (Copied or not.)