So, lets start of with bungies “Halo: Reach”. The campaign was nice, but there was no WOW moment. It was shoot here, shoot there, mission complete. 343i takes halo 4 and makes the campaign absolutely amazing. in the prologue, there was alot of hands on things like when you opened the elevator shaft and climbed up the broken metal pipes, jumping to dodge falling debris. I cannot possibly say enough good about the campaign which i hope one day to play on legendary, although heroic suits my need for strategy while also keeping it fun and care free.
Onto war games. there is a much shorter explanation at the bottom if you just want a quick opinion
for me, nothing is better on a halo multi-player swat game than being on edge every second that you play on a map like reflection, and getting a double or triple kill (once in a blue moon i get an over kill). on reflection, there is a defined main floor, basement, and a battle ground hallway on the 3rd floor. you know the hot spots by heart and you have a strategie each and every time (at least my team did). keep the battle ground hall way. On halo 4, complex is a map i end up playing on the most. there is no 1 defined battle ground where you know to keep a close guard. i would say 80% of the game i am sprinting because on swat you have only 4 enemies to find in an extremely large map. every map on halo 4 is over sized except for ragnrock because ragnrock is hemmorage from halo 3. this is exactly why i dont play war games. the maps are infuriating when there is no strategy except for run until you get to shoot somebody. the maps are rather to complex or just to open especially for a 4v4 game play. getting a double kill is doable every once in a while but a triple kill is hard to come by because with such a big map its hard to find anybody. did i say that enough? too big of maps? okay just making sure. everything else on swat is fine. maybe change the ranking system cause its kinda weird to not have to work harder to get from a level 1 to a level 2 than to get to a level 40 to a level 41. and bragging rights are better when you say im level eclipse now instead of im level 40 you know? 
SHORT EXPLANATION
great graphics, to big of maps, to many random buildings, no defined battle ground, 80% of game is spent running in search on a single enemy.
in halo reach, 343i was my hero. they made great additions to bungies already great game and i couldnt help but feel grateful that a company with THAT great of ideas was going to make a halo game all there own. when it came out, i played campaign first like i always do but instead of playing war games(like i did for reach), i simply played campaign over again out of frustration of the maps. i promise that if 343i makes a regular swat playlist, and a swat forge map play list that the loyal halo fan base will come back. the over sized maps are exactly why there are currently (as of 10:38pm EST 2/5/2013) 19020 people playing big team infinity slayer and only 7389 on SWAT. i would tell you what halo reach has but sadly i broke my halo reach game because i was mad that bungie dropped halo. HA no normal ware and tare. also my dog ate it XD.
BUT SERIOUSELY- best campaign ever, dont know why that didnt translate into great war game maps.
this isnt to bash 343i. im just not a fan of the maps.