1. Make radar more important. If possible, I'd suggest that losing radar also means vehicle dar box goes away, too. To counter that, you could add four more auto AA guns (one at each corner of the radar tower) to help protect it a little better.
2. Please, for the love of all that is holy, put a time delay on people who switch sides. I am really sick and tired of fighting against guys and then in the same battle they're on your side, and vice versa. A 30 minute delay would be great, but please go with at least a 15 minute delay. Please. This double agent crap really, really sucks.