See: previous post. I can have tt up with 5 seconds of voneroubility, and can use a combo of e2s/tss/polarize hull/aux 2 sif to cover that weakness. Trying to get good grav sci's so my gw/ss/ sensor scan combo can get better. To beat gates, do what you would with a cube- get on top of it, rotate tanking abilities, draw aggro, and leave the gate open to escorts with the dps to finish it.
I can usually tank one side on my own using my Oddy or Excelsior re-fit, especially the Oddy if I use the universal Lt. Cmdr slot for another science officer, but my DPS isn't quite that great to destroy everything so I normally am only able to take out one of the Transformers by the time the rest of the team is heading my way. In a cruiser though what I've found works well for helping take down the gates is to park broadside about 8-9 km out and spam EPTW and weapon batteries.