FWIW, I've installed ~50 RadioRA3 Sunnata dimmers & switches in my home (~60% of loads) along with a handful of keypads and several motion/occupancy sensors. Generally quite impressed with the RA3 operationally; it's highly reliable, as expected, and the day-to-day UX is second to none (and I personally like the aesthetic & have received compliments on it).
The software side is lacking on Lutron's side; the software itself is somewhat cumbersome although also relatively straight-forward & easy enough to figure out -- it mainly just feels a bit clunky & old-school, but it works & is even relatively obvious/intuitive -- may need to occasionally look something up but beyond that, the training wasn't even overly insightful & was mostly sales training (the setup flow reminds me of Insteon config via the macOS 'Indigo' app)
The primary limitations I still yearn for are things like conditional and/or time or mode -based actions -- none of which can be done with RA3 out of the box.
The main things I want to be able to do are relatively simple, basically boils down to being able to have >1 time-boxed (or could be mode/variable -boxed, or whatever -- a single simple logical evaluation). Basically I'm not seeking wizardry, though would probably play with it if available, but I mainly want to be able to have motion-triggered loads (motion/occupancy/vacancy) react distinctly based on time of day.
What I want/need is mainly for "master bath" -type scenarios:
Where motion-driven ON is amazing, but you really don't want 100% brightness in the middle of the night, and if you set the "ON" level to 40% all the time then it's actively annoying in the middle of the day when it forces you to go hit the switch manually to get to 100% brightness to be able to see. Having to physically use the dimmer during the day but NOT at night is counterintuitive; you want a consistent routine, either you always use the dimmer or never/rarely use it, having to use it during certain times of the day is frustrating.
FWIW, Lutron does have conditional logic & variables but not in RA3 -- they (presumably arbitrarily) constrain that their higher-end (and dealer-only) "HomeWorks" product line.
I've setup the HA integration with Lutron and it works as advertised, which is pretty flawlessly; you can achieve the conditional logic with it, though with a bit of added latency (and at the mercy of HA's overall stability). It does work, though.
Unfortunately, HA is a good bit more of a PITA and substantially less long-term reliable vs Hubitat, at least in my experience. I've had to manually reboot Hubitat maybe ~3 times in 5yr (and I suspect that was largely due to 3rd party code/plugins). For HA, I've had to manually do something with it >20 times in the ~2yr of having it be semi-actively involved in portions of my setup.
I've yet try any HA<=>Hubitat integration WRT the Lutron stuff; I do have some "bridged" integrations setup for Unifi (cameras/doorbell), but those haven't been overly confidence-inspiring on the long-term reliability front either.
I suppose I might just need to dive into the code, if no one else beats me to it -- it seems like the low-level library is readily available & relatively stable/functional (and I'm a developer). I've just yet to be pushed to dive into any Hubitat plugin/library code personally; I have a sneaking suspicion that the existing open-source code (Python library) may not "just work" trivially on the Hubitat, and might require a substantial bit of porting -- which doesn't sound like the most fun way to spend multiple weekends. 
Anyways, FYI -- I, for one, would be willing to pay a nominal one-time fee to get built-in Hubitat support for RadioRA3. I'm not sure how stable the LEAP protocol/API is but, if needed, I'd even consider paying a reasonably-priced subscription for it (i.e. maybe $60-$120/yr, or so?).
On that note, I'd be curious how many RA3 users there are & if others feel similarly; I'm not wholly opposed to taking on a project like that if it could conceivably be ~neutral value proposition (and scratches my personal itch).
