^ i found this guide to be really helpful... here's some stuff from it about the stats:
"17) Stats -
* Might increases the damage of your powers. (no longer increases healing) * DPS and Precision increase the damage of your abilities and weapon attacks. * Defense increases mitigation in PvE. * Toughness increases mitigation in PvP."
"21) Current Stats & Descriptions that effect powers, abilities and weapon attacks.
Note: These are found by going to your inventory tab (i) and clicking on the stats tab.
Health:Health measures the amount of damange you can take before being knocked out. Enemy attacks can reduce your health. You automatically begin regenerating health when you leave combat. Power: ower is required to use super abilities and is drained as they are preformed. Power is recovered quickly when using weapon attacks to drive up the hit counter. Power returns slowly when out of combat. Defense: Defense reduces the damage received by attacks made by non-player enemies. Might: Might increases the damange and Health recovery effects caused by super powers. Restoration: Restoration increases the potency of all Health recovery effects you activate. Vitalization: Vitalization increases the potency of all Power recover effects you activate. Precision: Precision adds to the base damage caused by all weapon attacks. Toughness: Toughness reduces the damange you receive from attacks made by enemy players. Dominance: Dominance makes your control effects such as stuns harder to escape. Dominance increases the damage an enemy must take before control is broken."
"22) Stat Formulas
Precision: 10 Precision = +1 Weapon DPS Might: 4 Might = +1% increase in base power damage or healing Restoration: 4 Restoration = +1% increase in base amount healed Vitalization: 4 Vitalization = +1% more power generated by any effects you cause Dominance: 2 Dominance = +1 additional damage an enemy must take before control is broken Defense/Toughness: As you gain levels more Defense/Toughness is required to maintain the same protection. Roughly 15 Defense at level 1 and 71 Defense at level 30 = +1% more damage prevention.
There are hard caps but you shouldn't be able to reach them. They are more or less just there in case the devs flubbed up somewhere."