Different things work for different people, but I like Lutron very much and those are the switches I have in my own house.
As far as getting past the 50, I think it’s fine if you occasionally have some Devices of other protocols, I have a couple of Bluetooth switches for three places where I wanted it quick and easy solution and I didn’t want to pay an electrician for wiring.
But another alternative that some people do with big houses is just to set up one smartbridge per floor, giving each its own account. Whether or not that works for you just depends on how you plan to use the system.
I’m tired now, other people will have to continue the conversation from here. 
Also, just a reminder to everyone: I don’t read the private notes much.