PvP is currently heavily slanted towards Klingon for simple fact of cloaking. This power is so easily abused, that even 'counters' such as sensor scan and tractor beam are only soft counters.
In well over a hundred pvp games, I've never been caught in stealth approaching the enemy. Not ever. It's so simple to avoid detection that you have to be trying to be seen. I see fed players drop mines and just laugh because that is simply a waste of a weapon slot for pvp. No cloaked player ever flys into mines unintentionally.
The fedball tactic is a simple byproduct of cloaking. Ask yourself, what do you do when you can't find the opponent? You group up. Safety in numbers and you don't know how many enemies are out there or where they could be. You don't even have the capability to find them. You simply have to wait for them to come to you, and they will.
When I attack with the pug it's always the same. Rarely do any of us ever team, we all know the drill. Target the weakest looking ship while the first person tanks. Usually I open because I'm a cruiser. Feds have almost no chance unless they instantly disable this player (me). If they don't, reverse shield polarity will give even the worst teamates enough time to focus down at least 1 target, at which point all moral is broken for the federation as any enemy that might get low simply blows a speed battery and evasions away to safety (if they don't have battlecloak). Even heavy focus fire it's difficult to take down a smart Klingon player.
Anyway, simple tactic. Usually the fed team wipes 5-1 or 5-0 and once they're spread out it's gg. Most of the time a couple have flown back during the fight and die to add up the tally not realize the battle is over. At this point very few battles continue as everyone just wants the game to be over so the federation proceeds to feed. They'd rather not have to deal with the cloaked attack again, they'd rather just take the loss.
Anyway I'm guessing my win rate at least for the 5v5 batles is around 80-90%, with the few losses being from games that were already over before joining.
I think that the cloaking playing field needs to be leveled. There are a number of methods including adding temporary vision locations/items on maps. They could fix Mask Energy Signature so that at least a couple weaker ships can stay hidden from the initial onslaught. They could also increase the sensor vision of all players. Honestly, all cloaked ships should instantly be detected around 5km in my opinion. Make it at least take some skill to use cloak.