Okay, you are referring to the PCV Valve. Got it!.. Just got our first 2015 CT with 101,000 -- What do you guys suggest I do for maintenance?
I would start with the basics. Oil, air filter, cabin filter. Check brakes/rotors. Check tire depth. Make sure all your fluids are topped up and you aren't loosing any when you drive.
If you don't have any problematic symptoms I wouldn't touch the water pump, EGR valve, engine coolant, inverter fluid, brake fluid. Check the battery fan screen in the rear passenger side seat. Make sure that's free of debris/dust. You're also still early for spark plugs.
If you feel like doing it yourself, you can clean just the EGR valve and put it back on the car. The PCV/Check valve is behind the intake manifold, which is separate from the EGR valve. You can clean it, but I wouldn't do it right away.
The car honestly doesn't need a whole lot to maintain it.