Until I've played this map or read some comments about gameplay. I feel like it will be either a massive camp fest/spam fest/turtle fest.
Camp fest: Team will push other team back to spawn and since you dont need to actually push the cart the team will stay.
Spam fest: Later into the game people realize that dying is bad (worse than before). Most people will play defensively, stay at range and never really dare to push in and kill some people, will just be a bunch of nade/rocket spam and sniper fights.
Turtle fest (worst case): Teams will turtle and wait for the other team to attack. Which will lead to the turtling team winning or the other team does the same -> stalemates (reminds me of pipeline s1 & s2).
Just some bad scenarios that popped up in my head with a gamemode like this.
An idea for fixing it would either be some badass map design to prevent this, or to just let teams be able to push the cart (though it would ruin the gamemode idea and incourage turtling). Meh, I don't really know until I've played it, just how I felt.
Might wanna come up with a better name <.<