nothing else needed other than upgraded firmware available from support. They do get hot and there is a warning about putting them in enclosures. I don’t think there is any limit. Yes you can operate them independently just like any other smart device. You can turn them off both at the switch or the app. However, if the switch is off the app won’t work.
Also, if you switch them off or on from a physical switch (cutting or restoring the power), the bulbs do not send that event to the Smartthings hub. So it’s quite possible to end up with their state “out of sync” with what Smartthings thinks it is.
I think there was another thread that actually had a draft device type in it, I just can’t seem to locate the thread right now. I don’t think it started as a GE link thread is the problem. But maybe I’m wrong.
I’ve asked around about “off” updating based on non-returned pings (both here and directly to ST support), but I haven’t been able to find any leads. Modifying a device type to that extent is above my pay grade for sure. I’d be very curious if there’s a solution out there.