it’s not a matter of long list or short list: just a matter of matching up what commands it supports with what commands SmartThings can process.
The basic thermostat stuff should be fine, that’s like any other basic Z wave thermostat and SmartThings does pretty well with those.
The Association could be fine, could be a problem, as SmartThings only does very basic association, and if this device requires associating with group one for certain commands and group two for other commands it probably isn’t going to work well with SmartThings, at least not without custom code.
This is the problem people ran into with the Fibaro motion sensor. The SmartThings hub will only include itself in Association group one. So if you need to do anything with other association groups you have to do it through a smartapp or a really complex custom device type. It’s not impossible, but it gets tricky.
I believe “thermostat mode” is just a number that get sent. This is how you change your device from “heat” to “cool” to “auto” to “fan only” etc. different thermostats offer different options, and that’s fine. If it’s just a number that get sent, the fact that “two” means “heat” to one thermostat and “fan only” to another thermostat is no big deal. Zwave is only responsible for delivering the message, then the thermostat itself acts on it. “Thermostat mode” is also how you usually send an off command to thermostat. So I haven’t looked to be sure, but I would guess that thermostat mode is one of the command classes that the smart things hub does support. Again, just look at one of the device types for one of the officially supported Z-wave thermostats and see if it’s there.
I’m not sure about the multilevel sensor and the power level. The best thing would be to look at other supported zwave thermostats and see if they have those command sets. If they do, you’re probably fine. ( I can’t actually read device type code because reading groovy with text to speech software is a total headache. But other people in the community will be able to help you.)
“Manufacturer specific” is always an unknown until you actually try it or you talk to the manufacturer. Usually that’s where they add their advanced features that only work with their own controller. But it may be that you don’t need those.