The badges need changing. There's no real reason i can think of to have so many differing levels of them. If you're worried people might grind the t1 exploration missions just lower the reward and cost for the lower rank items. It's not hard.
Not sure if you're a Klingon or Fed but when us Klingons hit 21 or whatever the level is (Not sure) we lose the easy mod Kahless expanse and are pushed into the Nebulas. The Nebulas arent all to hard either but you have to choose you fights a little bit more.
Note: I can take like 5 typhoon battleships in a tier 1 BoP. I'm not saying nerf it but cmon.