Here is a thread where I wrote about the same issue.
The problem is not with the number of players available at that time.
The problem is matchmaking.
One game I will play with 70% players, the next game only 5 players. Where did all of them go? Well may be they are in a lobby with another 5/6 players. Doesn't make any sense. BF4 handled this very well. Never had a problem with just xbox360 players.
Standard servers with map rotation and sever browsers will fix the problem. The lobby/match making is a step in the wrong direction trying to fix a non existent problem.