I would be in favor of tailoring bosses so that each one is best locked by a particular class. For example:Yes ss sorry
Leave qs as is
Give ss a cast time to eliminate all rogue ss lock grps and remove poison resists from everything like before
rogues: make it have no poison resist and weak against pierce damage. Basically the way most bosses were in the past.
Warriors: make the mob weak against blunt damage. Skills like pummel and such can really do a good job of locking. Make it resist pierce, fire ice and magic quite well.
Rangers: give it some really tough and fast mele. Make skills like entangle really necessary, perhaps by making it unable to be damaged easily unless it is. Definately make it unable to be tanked so that bola are needed. Give it a low movememt evasion.
Mages: make it weak against fire and ice damage.
Druids: make it weak against magic damage. Possibly make it necessary to root. Give it a bad aoe skill that can be reduced to tolerable by the right ward.
These are just some general ideas but it's already possible to make bosses not just a rogue lock fest. Obviously it wouldn't be fair to have a key boss like snorri be rogue only so perhaps there could be a few types that could spawn.
It seems otm has tried to fix this a bit already and some event bosses already have a few weaknesses As shown above.