whirlwind pvm barb help

ok..this is what i've got so far. at lvl 79..i have 8 skill pts and 35 chr pts unused.
sword mastery, BO, WW: 20
everything else has only one point in it.
now, i want to be able to take out bosses too. Should i now max berserk or go 1/2 and 1/2 in conc.
Also, my items are currently: 398 botd cb eth. perfect upgraded arreats w/ 40ed jewel, 7/6 vampbraces, 2x 5% bk, verdungos, eth stormtrek, stormshield (still don't know what to put in it since my resists are all 75), 26% maras. and my charms are 1/2 masteries and 1/2 combat.
My might merc is using: bramble archon plate and ethreal gaze. I'm not sure what weapon to put on him. Eth DOOM crpytic axe or dual amn eth bonenew (295% ed)..bonehew is good cuz of the leech and nice dmg. DOOM adds the holy freeze. But i'm not too sure if having holy freeze along with thorns is a good idea. because then thorns will not have a good effect. the idea of thorns is for ppl to hit you, they barely hit the merc if you have holy freeze on.