In regards to comments about PI being ok. I feel like they're missing the point. WHM's identity is centered around two important abilities. First one is Cure III, second one is HoTs.
HoTs already have a very limiting factor in that unlike shields they are rarely effective healing outside of a very controlled healing environment. WHM has ALWAYS had an issue with HoTs not being able to express themselves and being crushed by other healers (or mehanics that require topoffs). When you medica II for example, it's only worth it if you let your hots tick and this again only happens in very controlled environments.
PI goes absolutely against this as it helps you crush your own hots in many cases. It was never intended to do this in the first place and was patched that way because WHM abilities were a trainwreck. The only reason PI is "ok" currently is specifically because the hots are kinda pointless and that's an issue (or the occasional situation the timer isn't too short but these can be replaced with [spirit consumption]). I'm not saying the skill isn't currently useful, I'm saying it's counter productive for the intended class gameplay. It goes against the class identity.
Also, saying it's intended as a tool for maxing heals in an optimization setting is underwhelming at best for a lvl 70 ability and should definitely not lock us out from an altogether different mechanic with it' own set of opportunities for optimization.
And to close this off. You can't complain about Lily generation rates in a vacuum. You must take into account the trade off from the lily skills. If your 5 lilies allow you to cheese 5 mechanics in the fight, that's going to be about 1/4th of the mechanics in a 9mn fight (at a rate of one every 30 seconds). It's huge.
The current generation rate is absolutely fine considering we have no use for the lilies (ironically). It'll only need readjusting once the lilies actually have a use.
This is a good remark but also assumes changes to how stacks are generated and how long they last wouldn't be made. The ability to stack on the tank could solve this. The numbers I posted aren't absolute and would need adjusting. The damage taken depending on encounters does vary from 3k for your dungeons to ~7kish for your average savage (15kish for outlyers like god kefka where you're capped by enmity anyways). This gives ample opportunity to make it more useful than PI, even if it won't scale evenly doesn't mean it should be discredited as it is ok for your class to be stronger in some encounters than others, we see this all the time with mobility.I'd actually argue that your thorns mechanic would actually fall foul of the same issue whilst also being a balancing nightmare. It's likely to be useful in an even narrower band of encounters vs the current PI. In more casual content with minimal aoe it's just not going to amount to anything without ramping the percentages right up which in turn would blow it out of proportion in high end content when the aoes come rolling in.
I'll look forward to your take on the gauge though.