Hi, I'm a barb
Realistically, life reg vs monks doesn't play such an important role, it's all about the burst damage of monks, like u probably saw manner on ptr, good monks still kill him.
Top wd like blud or euronymous I bet will still beat consistently any barb, especially with the new bats damage, which is insane.
Barb v barb is much easier to tank 3 crit rends and the future will be stun hota and maybe rend too.
The DH and wiz are the real problem.
Good wiz are able to disable barbs for an extended period of time and RoF buff with warcry banned might be enough to negate the life reg buff. I'm thinking maybe banning ignore pain too or instead or warcry, but testing is needed vs the new RoF.
I know that nofear complained about Shadow88 finding a great build vs barbs, but I had no problems vs him, using warcry, so the wc ban is needed.
Vs dh is more tricky, wc ban already nerfs fury regen too much and legacy Nat can stalemate forever if they can't kill.
Overall when nerfing barb ehp I suggest banning passives like relentless and nerves of steel maybe also superstition and tough as nails vs certain classes, not fury generating skills which actually leads to more stalemates.
I'm sure that a solution can be found, but it should be extensively tested by the top players with close to optimal gear. not top gear vs average gear like in a lot of the league games... which can be misleading.