While I havn't done extensive testing on this, I think I've done enough to answer.

1) From what I see playing, I get roughly 4-5 times more damage. This is dependant on the damage you're dealing and the targets damage resistance, so captain skills, buffs and debuffs and traits like teamwork will modify the damage.

2) Roughly 6 seconds. AFAIK there isn't a way to increase/decrease the time however there are kit powers and devices that can clear an expose from you, I can't remember them off the top of my head but the description will say whether or not a kit power or device clears an expose.

3) Not that I've seen, certainly not in the way hold/kb/etc resists are handled. I run an expose-heavy build and have hit an exploit attack on a tough enemy and exposed him right away afterwards.

I'd just like to point out that the Telepathy trait increases Expose duration (by 1 second for Basic, not sure about Limited/Superior). I like to have one or more of my BOs on any given Away Team be (Superior) Telepathic whenever possible.

Also having the Luck trait improves the chance at starting an Expose, as well as improving Crit Chance.

I know that in PvP, there are Science toons that appear to either clear exposes instantly, or have some sort of passive protection. Not sure what kit they're running, but there is definitely something that reduces exposes (other than the shield consumable).

Been a while since I used a medic kit for any meaningful period of time, I'll look into this.

Sorry it took a while, here's the science kit powers that remove exposes.

Vascular Regenerator
Medical Tricorder
Nanite Health Monitor
Biofilter Sweep
Hypospray - Melorozine

Also, Rally Cry (tactical Kit power) and shield charges remove expose effects.

Extremely helpful thread! Thank you so much for taking the time to write it up! Kudos!!!

In STFs its helpful but dangerous , but you need to flank,flank and flank.

Very helpful and humorous. Great job!

Well this is a ballache.

Excellent and entertaining guide, good sir!

Although I will add, I personally am a big fan of melee combat. Melee weapons are especially handy when fighting the borg, if you have multiple heal abilities to see you through: because the borg can't adapt to a blade! I carry my lirpa for the borg. A few critical flanks and a Heavy Tactical down! [Then again it might be the rapidly combo'ing piano fingers...]

Sadly I'm not sure where I tossed all my Devidian armor/shield/device prizes but apparently they were useful... :/ I wonder if I can replay the missions to get these prizes again...?