So I've only been playing four days

got my lt commander and tier 2 ship (U.S.S Hawk) yesterday
I've engaged The Klingon's, The Gorn, The Borg (Once), And others for a brief moment but I was wondering IN THIS GAME what's the enemy you most fear meeting? and does it differ in space and ground?
So far with my very limited experience I've found the Klingon's the hardest foe mostly on the ground (I always try to ambush the groups with the swordmaster because taken them from the front always seems to get me killed xD) but I would love to hear views from Veteran players
Comments
The best way to deal with that is to try and find some way to avoid them or get them off of you and onto your BO's, even for just a moment...
Then move quickly to some place where you can hide and rejuvenate.
I've found that while you are powering back up, your BO's can usually keep those two busy and survive long enough for you to attack again from a better more distant place, to finish them off.
Of course, if they are ONE-SHOT HARRY's, then there's pretty much nothing you can do but move on and drop that mission.
3 of my BOs in any away team use bat'lets - only healer don't
If there is more than one melee mob - send tac + healer to one of them, other 2 BOs to other one.
Try to kill tac+heal attacked one 1st...
Captains also have bat'lets... so can take melee for short time (Sci one longer than other with self heal).