Its not per se the number of maps that is a problem, but more the kind of maps and how some play.
The 3 BTB maps are more diverse (Deadlock being a Banished map, Fragmentation a Forerunner map and Highpower a human map) then the 7 4v4 maps (Behemoth is Forerunner, the rest is all human structures). More diversity in style is needed for the 4v4 maps. With the Forerunner and Banished structures being central in campaign and no human structures being there, it’s a bit weird to have almost all 4v4 maps being human. I like to see a 4v4 map where you play inside a Forerunner or Banished structure.
Aquarius (4v4)
This is actually my favourite map. It plays good with a good mix of the more open parts and smaller rooms in the side. Slayer, CTF and Fiesta are all fun to play on this map.
Bazaar (4v4)
Okay’ish map. I like it more as a CTF map then as a slayer map personally, but it is okay to play. The marketplace (middle of the map) only feels a bit to much of a ‘enter it and get shot from all sided’ spot, since almost all path go through this open area. For FFA i think this map is bad, since the powerweapon is still in, but a players spawns near it, making that player have a huge advantage from the start…
Behemoth (4v4)
Personally i don’t like this map at all. It is way to much open area and way to little close spaced area. Most spawns are also in the open area with no good weapon pickups nearby (BR) for that open area, making you have to walk out in the open without middle/long ranged weapon while enemies with BR and sniper just firing upon you… Fiesta on this map is just bad because of this, since you can spawn with only close range weapons, with enemies with sniping weapons… You got almost no where to go then.
Deadlock (BTB)
My least favourite BTB map, though still decent to play. The two banished turrets make it so that in the beginning walking down the middle path is just suicidal most of the time. It also makes it that 1 teammate just camps the turret in objective mode, while not contributing anything (because the objectives are out of the range of that turret). Also most path are to small and rocky to be able to use the vehicles. The wraith (when it spawns) can hardly move away from the base because of that. That it plays in the dark makes the map stand out most in my opinion.
Fragmentation (BTB)
The two bases feel a bit nostalgic, the rest of the map plays different ofcourse. Overall a decent map. The entry to the top of the tower in the front (from sniper spawn) does make it so often the back of the base is not (fully) used. That entry might be a bit to much though. The addition of the two vaults in the side that you need to unlock for the powerweapon is nice and adds a new element, but perhaps the door shouldn’t close while there is still a player inside, this makes just AFK-camping in there to much of an issue. I think the doors should open automaticly for everybody 10 seconds after entering or when the powerweapon has been grabbed (to only close again when no one is inside anymore and only then the powerweapon can respawn).
Highpower
Overall a nice map, but from 1 base you have a bigger line of sight then from the other, because the ‘gate’ is closer to one base then the other. And 1 base has its vehicles spawn in the back (covered by the base) and the other to the side (visible from the middle), wich also makes it to much of a difference wich side you spawn. This map plays better with vehicles, although the giant hole in the middle is a bit of a shame. Would perhaps been nicer if that was just an open area?
Launch Site (4v4)
Okay map for one flag, terrible map for anything else. For One Flag the biggest problem is recovering when the flag is already dragged to the gutter. The defenders have only 1 vehicle (mongoose) wich makes it impossible to gain the enemy when they crossed that point. Replacing the mongoose with a gungoose would already help a lot.
For slayer and fiesta this map is just to one-sided, because of the vehicles (and also to big). In slayer the hog and ghost are creating just to much of an advantage and in Fiesta those could even be a scorpion or wraith. I always went on a 10 to 20 spree before the enemy could kill me in it on Fiesta, wich always decided the match.
Live Fire (4v4)
Decent map. Only with oddball i have a little issue with it. The team that spawn at the towerside has a little longer path to the oddball (since the other team has an almost direct path) and if your team has the repulsor, the tower is a bit to well defendable position, making everybody want to bring the oddball there.
Recharge
okay map, but the powerweapon is a problem. The most effective counter to this weapon, the repulsor, spawns near the sword/hammer, wich often leads to the one carrying the powerweapon also having the repulsor. When the powerweapon is the sword, you often see the swordcarrier just run across the map carefree, since it is almost impossible to kill him in time when he is sprint-sliding towards you. The repulsor shouldn’t spawn near the sword/hammer. At the same time, most people don’t use the middle of the map (where the oddball spawns) in slayer, because you can get shot from all possible sides and there is no incentive to go there. Perhaps make either the powerweapon spawn here (and move the repulsor to the little island where the powerweapon is now) or move the repulsor to here.
Streets
Okay map to play, but biggest problem is that one side spawns with the BR close and the other with a commando, making it uneven.