During a casual game we tend to use focus as the default action if someone discovers belatedly he/she forgot to take an action. After all, every ship can take focus and it is definately not a bad choice.

However, I do have a preference for the more aggressively inclined Target Lock or a Barrel Roll for positioning. One of my problems playing Empire as they don´t have Target Lock on most vessels. Evade is the least used one. Most of the times I have used it I wished for a focus token or barrel rolled away.

So the rankings are:

1. Target Lock

Barrel Roll

2. Focus

3. Boost

4. Evade

Focus is the default action if i'm not doing anything else.

Boost and Barrel roll are both fantastic for arc dodging. I love them lots.

Target lock... eh if i am using warheads yeah, if i can get it free from a proc, yeah otherwise i seldom bother.

Evade. I very rarely use.

If I had to rank my list would look something like:

focus

boost/barrel roll

target lock

evade

But obviously this is al situational.

One good use of target lock is in situations where you are disengaging momentarily. If you aren't shooting or being shot at that turn, a target lock is often your best choice, because you can use it later - remember attack dice modified by focus+TL (which you would have the next time you're shooting at that target) are immensely powerful. I would even recommend it in certain situations over a defensive focus.

For example a B-wing with a on it's tail at range 2, and no damage on the B-wing. You have no shot, so the focus would only be good defensively. But, the most it is going to net you is one shield less damage, and that result is not terribly likely. Taking a TL and saving it for your shot next turn instead might be the better choice.

Obviously the choice changes depending on the situation (if you had only a few hull remaining a focus would be better, for example).

In short, don't underestimate the advantage of TL's persistence.

It is tough to "rank" them as it depends so much upon the ship performing the action and the situation it is in. But I'll give it a go...

1) Focus

2) Evade

3) Barrel Roll

4) Boost

5) Target Lock

Order by Usefulness

1) Focus

2) Barrel-Roll

3) Target Lock

4) Boost

5) Evade

Order by Opportunity would be the reverse of the above list.

Evade is at the top of the opportunity list because of the limited situations it is beneficial to use the action. Which is Turtling or you're in Range-1 of an opponent.

Boost is second because it can potentially move you into R1 of your target

Target Lock, third since if you have Ordnance you probably don't want to explode without firing it.

Barrel Roll, fourth because while lateral movement is great for arc dodging. Offensively it won't generate a R1 shot as often as Boost.

Focus is Last because if the situation doesn't call for the above actions focus does well Offensively and Defensively. Also the above actions could be considered "high risk, high reward" actions whereas Focus is "safe" which is why I consider it most valuable but least opportunistic.