I was pleasantly surprised with 558 and how well I could see the pitcher's mound and the pitcher's delivery towards home. We were high enough to me able to see every nook and cranny of the field and still close enough to hear the Umpires grunts and Super Indian fan John Adams banging on the drum in the outfield.
Some foul balls do reach this area on the occasion, I've seen it happen myself.
If you can get a seat in the 400s, those are just like these seats but are much smaller sections down in front that won't require you to climb hardly any steps to find your seats. The ushers keep a pretty close eye on those seats since they're a little more expensive.
If you absolutely hate sitting in the 500s, you can always opt for the not so comfortable bleachers. But they're field level and most times, fans just enjoy sitting closer to the action and don't worry about comfort or view of the surrounding area.

You can often find free parking in the Great Lakes Brewing area which is a decent hike to the stadium. You can also ride the light rail into downtown, there are two or three locations to get off at. Gateway East, I think is the name of it, is the most convenient stop and will allow fans to utilize a skywalk to walk into the ballpark. There are only four gates that I know of, Gates A thru D.