Feigao 7L, Warrior 9920 + 12 GP 3300 cells = hot?

Dropping down to 10t would do something.

Problem is, I'm in Germany and if stuff gets stuck in customs it's a big hassle to get it.

Do you think adding a receiver pack would help?
Apparently the BEC in the controller produces some heat which could be the reason for my problem.
I don't like adding another battery too much, but it'll be interesting to check if it helps.