I'm not Michael, but I can help you somewhat. It depends on several factors - stadium location, day of the week, game time, parking availability, proximity to public transportation. Depending on the city, it can vary from a "piece of cake" to absolutely ridiculous. You have to research each venue for specifics.
In large cities with downtown stadiums for weekday evening games, it's almost always pretty rough, because you will be competing with the normal afternoon rush hour getting there. If it's an afternoon game, you will get caught in rush hour leaving. Some of them have ample parking and close access to the freeway system, but others have neither. With some parks, I would advise you not to even try to drive to, public transportation is the only viable option. Wrigley Field in Chicago is one of those, it's nowhere near a freeway and parking is very difficult and expensive. There is a light rail "EL" station 1 block from the stadium. When I lived there, I parked out in the suburbs and rode the "EL" in. However, US Cellular Field has a huge parking lot and is located right at a freeway exit.
Try to choose your hotels with these factors in mind - where possible, I'd leave the car at the hotel and take public transportation for the least inconvenience. This also minimizes the possibility of getting a DUI if you like to drink beer while watching the game!