The City of Lights! Can't go wrong with Paris.
Where in Easter Europe do you recommend to travel to?
I have to say none at this time..
Prague
As for Eastern Europe, I recommend you to think about Ukraine. You can rent a car there from one of the services, though I recommend you the one from https://ukr-prokat.com/en/rental-cars/car-rental-in-odessa and take a nice road trip around Ukraine. You will surely like its nature and people. Such a great country!