In my opinion, it will be worth your while to park in Newport or Covington and take the Southbank Shuttle to and from the game. Heck the shuttle has a stop by Mainstrasse, so you could park in their lot for free and ride the shuttle to the game. The key is being very early, because the shuttle will probably be delayed because of traffic. You could also flag down a cab; which may cost a little more but will be quicker.
I can’t say for sure, but if you park in Cincinnati you can expect wait times after the game to be much longer. Generally, the Kentucky side provides quicker access to the interstate for a really crowded game. The moral of the story is you probably don’t want to get stuck in some 10 story garage for an hour afterward.
Go Reds.