As an experienced and not too bad CoD player, after 25 hours of gaming time I'm done with the multiplayer aspects of this game.
Firstly the spawns are awful. This always seems a common moan with the CoD titles but in this one they're worse than ever. For example if you spawn in the main castle on the map Stonehaven you may as well commit suicide as an enemy is sure to wipe you out within seconds. And I've just played a game on Flooded in which we were spawning in a room with an enemy IMS. Genius. All of the spawns are the same; much too close to enemy positions.
Secondly by increasing the routes through the maps and giving every single room or alley at least 2 or 3 entrances IW have created the perfect rushing gun game. As long as you don't mind a lot of being shot in the back or being shot from 3 different angles that is. In short, most of the maps and games are absolute structureless chaos. Annoying and it turns the game into a button bashing exercise.
My next main gripe is that they've made the player models so difficult to see, especially considering the sprawling space. I did a comparison with MW3 and they're so much smaller and darker in the new game, and even the player labels don't show as soon and are smaller.
And lastly the icing on the cake, the final nail in the coffin. Dogs that can't be stabbed, that kill in milliseconds, and that take a full clip to kill. Need I say more.