I was thinking of model ideas I would find interesting and these were some of the things I came up with.
Brewmaidens
Heal/rez and buff bravery.
Runesingers
Buff/debuff unit similar to Runelords. Maybe chant to reduce enemy casting rolls. Maybe even once/game summon ancestor spirits for a turn like in Dirge of Dust and Steel.
Endless Runes
Self-explanatory.
Anvilguard
Hammerers-lite that synergize with Runelords (thinking along the lines of either improved Rune Lore buffs, or the ability to not count against a Runelord's 1 buff/turn).
Grudgekeeper
Hero that gives out combat buffs, esp when friendly models are slain. Gives much-needed potential to deal MWs.
Karugromthi/Living Ancestors
2-wound elite infantry, possibly with a Too Stubborn To Die FNP.
As far as Dispossessed weaknesses--I agree with most of that, but at the same time I do feel too that in a sense some of those disadvantages are what make dwarfs, well, dwarfs. We shouldn't be able to do everything.
I like the idea of rooting/slowing enemy units though. While the idea of speedy dwarfs is somewhat comical, I feel the alternative is very dwarfy; to basically tackle other armies down to our level. We're slow? Enjoy rune snares and cave ins, now you are too. We can't cast magic? Courtesy of excellent unbinds and ignores, you may as well not either.