Yeah, thanes need nerfing. But really, if you let yourself be ambushed alone and far from help by an organised group like that, you deserve to die. People should die more often anyway.
How much weaker can they go before it is a problem for you? Scaling handicaps will hurt the stronger players more, encouraging throwaway alts.
I really doubt I'll ever see that pendulum swing the other way. H&H encourages grinding for skills all day, and then not using those skills. People need every discouragement they can get against raising skills beyond reasonably attainable levels, otherwise PvP will never amount to much more than a chain of summons and countersummons.
The only purpose for having skills IMO is preventing use of throwaway alts, and the only thing that enables those right now is thanes. On the other hand, they are the great equalizer, so I'd be careful about nerfing them before other steps are taken to make the playing field more even.
Oh, and just remember why it isn't so trivial to beat a developed character with fresh alts - UA. You can't boost that, so the developed character will absolutely rape the alts with manoeuvres. Oak Stance in particular would be a tough nut to crack.