Is there a guide that says what powers are better than others? Or any 'must haves'. With so many BOFF choices and so few slots, it's hard for a newb to decide what to train BOFFs in.
No. not exactly. There ar eplenty of threads where people ask for possible builds for their ships, though.
It always seems to be a little boring to just suggest something and have everyone end up with the same builds.
Anyway, I have been thinking about making such guides in the past.
Things to consider in an Escort:
Your weapon choice dictates which type of powers you can use. In addition, the cooldown system for powers means what combination of powers make sense and what doesn't.
For example, it is not wise to load up more than 2 beam skills, as you can't use more than one anyway. The second can still be useful, as it allows you to use your abilities more often. But the third will be superflous, as the first power will be ready around the same time you could use the third. This is actually something that can be said about almost all powers (even non-tactical, non-weapon powers), but there are some exceptions.
So, with that in mind, you can conclude that it can be wise to use more than 1 weapon type on an Escort. But you don't just have weapon skills, there are also attack patterns, so that is a potential further slot. In addition, tactical powers also include one crew skill, Tactical Team. So if you have 2 weapon types, you can use 4 tactical BO powers at the same time. If you have 3, you can use 5 powers.
So, a typical combination can include
1 Torpedo Power (High Yield Torpedo is the best choice)
1 Beam Power (Beam Overload for spike damage is probably the best choice)
1 Cannon Power (Cannon Rapid Fire for single target damage)
1 Attack Pattern (Omega or Beta are usually best)
1 Team power (Tactical Team)
Additional Bridge Officer slots not filled yet can be used to double up on skills, and even pick more oddball ones. (or example, Cannon Scatter Volley is useful to deal with fighters , mines and other "pet spam", but it's not as good as CRF for single targe damage)
Now, there are additional considerations to make.
Attack Patterns and Cannon skills require Lt. or higher level BO slots.
Attack Pattern Beta debuffs your enemy, meaning it also helps your allies damage -but it's a hull resistance debuff, so its of less use against shields. Attack Pattern Omega buffs your own damage and helps you against shields and hull. Attack Pattern Delta debuffs enemies attacking you. The debuff is as good as the debuff from APB, but you somewhat lose your initiative with it - as you can't be sure the one you want to shoot at will be shooting back at you.
Tactical Team doesn't really improve much with higher levels.
High Yield Torpedo has a small "tweak" that HYT I basicaly is the biggest relative jump in damage, and due to the quirk with the damage being spread around all the torpedoes fired, the individual torpedoes in a HYT I inflict the highest damage (but adding all torpedoes, HYT II and III still deal more damage in total, of course), which means they can crit harder (though, as you fire less torpedoes, less often).
Torpedoes are primarily for burst damage, and you want to land hard blows against hull.
Beam Overload causes an energy drain penalty, which means you'll lose some DPS after your intitial spike, until that drain has recovered.
Beam Fire At Will and Cannon Rapid Fire affect _all_ equipped weapons of their type. That means whenever you mix in other weapon types, you will get a little less out of these buffs.
Mines aren't really good for damage.
Dual (Heavy) Cannons deal the most damage.
Overall, this suggests to me:
Don't use anything more than Tactical Team I.
If you pick Beam Overload, pick the highest ranking one you can get.
If you use Beam Fire At Will or Cannon Rapid Fire, you might not want to run more than 2 weapon types, but that would mean sacrificing one possible buff type.
Don't use Mines or Mines Patterns at all, unless maybe you like spamming up your enemies with mines. (Or he's using a lot of Beam Fire At Will)
If you use High Yield Torpedoes, use them with Quantum Torpedoes. Time your shots so you can expect to hit hull. Low levels of these skills are still very effective.
You probably want to use Dual (Heavy) Cannons as primary weapon.
You probably will have to decide between APB and APO, and not use APD as a primary power. You mgiht prefer APB when you use torpedoes, and APO when you use beam overload.
My own Build
That said, what I am currently running on my Tactical Escort is this:
2 x Tactical Team I
1 x Beam Target Subsystem Engines I
1 x Attack Pattern Beta I
1 Cannon Scatter Volley I
1 Cannon Rapid Fire II
1 Beam Overload III
1 Attack Pattern Beta III
Plus these non-tactical powers (a very defensive setup, with a glaring hole - no defense against Tractor Beams, better not tell that to my enemies.) But at least I never leave home without an Emergency Power to Shields, and neither should you.
Emergency Power to Shields I & II
Hazard Emitters I
Transfer Shield Strength II
I don't use torps in this mix, due to my "theory" of diminishing returns with cannons, but it means I am missing out one possible power in my alpha strikes (High Yield Torpedo). Also, by my own logic, I might want to try Attack Pattern Omega instead of Attack Pattern Beta, as I don't use weapons that I would time specifically for hull hits.
At lower levels, you can probably not really afford to run 2 or even 1 tactical team, you rather want a damage buff there. So High Yield Torpedo is an excellent choice you can start using even in your Miranda, NX-01 or TOS Constitution. (ALso in your Oberth, but would you fly a ship that was destroyed with a single torp as a self-respecting Tactical Officer?). Cannon Rapid Fire I might be the next skill on your list, then perhaps Attack Pattern Beta II/Attack Pattern Omega or Beam Overload III (Attack Pattern is probably better until you have 4 forward weapon slots)
And at endgame, you'll probably have enough skill points to retrain all your Bridge Officers to your preferred combination of skills and even experiment a few times. And if you don't, just keep playing until you do.
I would recommend to spend skill points during leveling only slowly and wisely until you sure you want that power. You can be better of training Emergency Power to Shields I to max on one of your Engineering BOs then to train Cannon Rapid Fire I on your Tactical...