Shes insanely great in terms of her kit and also keep an eye on main point - ubiqu debuff from her burst ;) no other source of that in GL atm and i wonder have JP some alternative or nope yet )
Looks like insanely great combo with Gregs slash res down >< ) epsecially considering she can steal time and he can both quicken and haste and both can dmg pretty well after that >< double element+slash chains looks like a meh in comparison loool
I rather use Sword Guard. She survives longer and will still be able to use her abilities.
Used berserker for a long time because it has a small (very small) heal. But she became a little useless while on berserker.. she deals a lot more damage by throwing her axe.
And of you make the math, probably sword Guard will save you more HP than fighting spirit would recover..