You didn’t mention iPhone or Android. I’m not 100% but I believe Android has a full feature set from purchase but iPhone doesn’t. Long coding will get it done but you have to do the work. It’s the better bet since I have read various problems from the apps. The apps do all the work for you, but they cost credits. I’m not familiar with how the subscription system works since I bought mine before it was implemented.
As for the changes staying, yes. Those settings are changed in the car, so nothing will change those unless you go back into to change them back.
As I mentioned above, I am pretty sure the pro gives you long coding access. Long coding is done on a module level by change bytes on or off to enable features, basically.
You can reset your oil life interval. I like the all windows down/up with the fob buttons. Useful on hot days by rolling them down 20 minutes before you leave. If you change your rear tail lights to dynamics, you can adapt the necessary coding to make that work. There are tons of options and pages of things to change. All the apps listed in OBD11 don’t necessarily apply to your specific vehicle.