Tanking: Why you should NOT be a tank in STO.

I love tanking. I've raid-tanked in many MMOs. (Massively Multiplayer Online games) It is BY FAR my favorite role in the so-called "holy trinity" of MMO gaming - Tanks, Healers, and Damage-dealers. However, STO doesn't provide a system where it is really practical to tank. Why do I say that, you ask? The reason is this: In order to be a tank, you need to be able to handle the extra damage that having aggro would provide and, of course, you need to be able to get aggro in the first place. Unfortunately, that is virtually an impossible combination.

 In order to get that aggro, you're going to need to compete for threat with players that are doing truly massive damage (Unless everyone you play with is not particularly good or well-geared) and that is virtually impossible without selling out for DPS (Damage Per Second) by over-investing in DPS consoles and Tactical abilities. The best damage in STO comes from stacking as much +crit hit, + crit sev, and +damage as you can. The more sources you stack at once, the bigger damage numbers you can reach. "No kidding," you say. The problem with STO is that you must choose between that console that gives +25% to shield capacity and one that gives +1% crit hit and +10 crit damage rating, with +5 weapon power. What ends up happening is that if you try to go right down the middle and get some damage consoles and some consoles that give +shields or +resistances, you're not going to be able to hold aggro off of the good DPS players. Not just the elite ones, but even the ones that are just pretty good. Damage scales too dramatically. In STO, you're really either high DPS or low DPS - how much resistance you have just doesn't matter that much.

Surely, there must be some way for a tank to increase threat generation and hold aggro, right? Not really, unless you're playing with a bunch of low-DPS players. (And, don't call me "Surely.") There are things that add to threat generation, but they have a cost: what you invest in +threat takes away from durability. For instance, there is a Fleet Science console from the Fleet Embassy that gives some serious threat increase (And, good damage for Beam Boats), but you're using a console slot that would be useful for universal consoles or +shield consoles. There is a skill that adds to threat, but every class gets access to the same skill and it's nowhere near up to the task of holding aggro by itself. Unfortunately, many high DPS players invest in that skill for the additional resistance it provides... because they always have aggro anyway. The problem really boils down to the fact that damage scales at such a high rate that, in order to get the damage+threat generation needed to hold aggro, you're not much tougher than the DPS players that are doing considerably more damage than you and really helping the team more by actually killing the enemies than your attempts to gain aggro could ever accomplish.

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Advanced Tip: If you are dead-set on trying to build a true tank, the most successful way to build a Tank is a Romulan Tactical Captain in a TSABC (Tal Shiar Adapted Battle Cruiser).

Why Romulan Tactical? Because Romulans are the highest DPS race and Tactical captains get Attack Pattern Alpha, which is the most broken captain ability in the game by a wide margin and will also have the greatest effect on your ability to hold aggro. No career path gives inherent extra resistance, hull size, or shield size - only long CD (Cool Down) clickable resistance abilities and healing abilities that you don't really need. Just go Tactical.
Why the TSABC? Because that ship is ridiculously tough with one of the highest Hull values AND one of the highest Shield Modifiers. (And, no, you can't Hull-Tank in this game. Too many bonuses to damage when a shield facing is down.) That combination, and the 2 Starship Masteries that give resistances, makes it the toughest ship in the game. Combine that with the Commander Universal BOFF Station, a balanced console setup with 4 science consoles (After T5U upgrade), defensive Starship Mastery abilities, and 8 total weapons - you've got a recipe for a ship with high Durability, Threat, and Damage potential. It also gets Sensor Analysis built-in. Oh, it cloaks too!
Why Beam arrays? Beams because FAW3 (Fire at Will 3) is a Beam-based ability and it is really the best for high DPS and tanking because it targets any/all ships and increases the beams' fire rate by about 50%. Arrays, and not Beam Banks, because Arrays have a 250 degree firing arc and slow turning ships have a hard time maneuvering to attack enemies with Beam Banks (90 degree firing arc) while moving. Movement is required to increase a ship's defense value. (Basically, defensive miss chance.) If you were pure DPS, set-ups using Beam banks can usually do a little higher DPS when they can stop and basically rotate to keep enemies in their firing arc, but you have to be constantly moving to reduce incoming damage as a tank, so Arrays will be better for tanking.

Advanced Tip #2: If you have a fleet-based team with friends that will work with you as a true team, they can use -Threat Fleet Sci consoles to reduce their threat and help you hold aggro. Don't count on this in a PUG (Pick Up Group) at all. They've all got to use the fleet consoles with -Threat, which means they've got to be in a fleet to begin with and know they should use those consoles.

The combination of these 2 tips is really the best/only shot at reliably holding aggro as a tank. Of course, that's a lot of trouble to go through when it's pretty much unnecessary to have a true Tank for any current content, and absolutely no need in normal or advanced difficulties.