The more I've played my PB in its Homecoming iteration the more I think I'm actually very happy with how it plays.
I don't really need Human form mez protection because Light Form is nearly perma (I have a t2 Alpha helping with that, but most of my IOs are generics) when solo and usually perma on teams.
I don't really need shapeshift toggle suppression because again Light Form has me Res capped without my toggles.
I don't need Human form Taunts because I can switch to Dwarf while in Light Form.
I don't really think the damage cap needs to increase. Warshades do fine damage with their current cap, the difference really being the pet far more than the Mires.
Single target damage could definitely come up. My preference for this would be to make Incandescent Strike shorter in animation time.
I wouldn't mind Glowing Touch getting some sort of secondary effect...+Perception maybe?
But I think the main power that is the culprit for PB underperformance (or PERCEIVED underperformance) is Photon Seekers.
Perhaps something could be done to improve the Seekers? Add a buff/debuff/heal secondary effect maybe?