So, version two, here are my thoughts:

It's much easier to get to the flag room, I barely see anyone utilizing the pressure plate. They're getting to the flag quickly and ignoring the plate. Pretty useless mechanic to me. Sure, it's cool to get there a little quicker with the help of 3 people willing to stand on the plate, but barely anyone bothers.

Since it's easy to get to the flag room with this mechanic, the flag room must be larger. It gets crammed up there really quick with everyone rushing the flag and ignoring the plate.

I like the mechanic, but there needs to be more of an incentive to go to the plate. Players get up to the flag room quickly without the assistance of the plate.

I have an idea. Add blocks and traps to make it challenging for attackers to get through. The plate (with 3 members on top of it) would completely stop the traps and allow players to reach the flag safer. Since attackers will continually die and get knocked off the plate by defenders, how about we keep the plate active for a few seconds after, and then have the traps pop up again until there are 3 players on the plate again? Maybe that would be too much, but it's something.