Manbearcat
Legend
Yeah, I'm more than a little perplexed by the resource balancing, here.
If "short rest" abilities should be thought of as "daily, unless you're lucky" resources, any perceived advantage to them disappears. And making them weaker (and they are) because of their refreshability no longer makes any sense. It tilts balance even more strongly in favor of daily spellcasting, where you get everything up front for the day.
The rest of your analysis was spot on, imo.
That is one concern that I would have (and a major one). However, equally as concerning is the (presumably) intended consequence on play. Instead of just the Extended/Long Rest pressure as a (metagamey in a bad way) primary locus conflict, we double down on that and get even more focus on nonthematic, metagamey conflict where PCs are trying to squeak out Short Rests and/or turtling because of too much heat (due to lack of encounter resources refreshing).
No thanks. I'd much rather just hand-wave 5 minute Short Rests, push back as hard as I can with their "encounter" resources refreshed, and focus play on actually interesting thematic conflict rather than a nonstop minigame where Fighters are trying to recoup their maneuver dice so they aren't boring or crappy.
Having a daily conflict over a singular Extended Rest? Ok. Having the working day driven by possibly half a dozen of these conflicts? Not so much.