Your setup looks good. Only suggestion I have is put ur thermometer in the dome too if theres room. And if its getting too hot (over 85°) just put a towel over your heating pad but under your propigation tray. It acts like a nice lil buffer so you dont fry your clones.
With the vents I leave them closed for 5 days then ill open them a 1/4 of the way. If they dont droop ill open thrm more to kinda ween them off the high humidity. If the droop ill close the vents some.
no dont put you're electric thermometer in you're done the rh will mess it up. ive fell for it. my rh went over 100 percent. good by meter. i know use an small old mercury one with a small plastic rh meter. i got them both for a quid each