I've played them all, numerous times, and Holler in the Hills is my favorite course. Period. It's more of a disc golf sanctuary with some really unique holes but it is not close to anything being in Brownsville. Lincoln Ridge (AKA Banklick) is a really great course, beautiful and 24 holes of guaranteed fun. Idlewild is beautiful and amazing but 24 holes that will leave you exhausted yet satisfied. Mt. Airy (across the river in Cincinnati) however, is an incredible course and is, unfortunately, scheduled to be closed come July 1st. So, if you can, I would go check out the legendary Nati Disc Golf shop that resides within the park and Mt. Airy before it closes.
I live in Lexington, KY (central) and there is nothing to see here as far as course gold. Another option that I have really enjoyed in the past is Freeman Lake in Elizabethtown. I guess it all depends on where you are going to be and what's most convenient. If you could choose anyone of them though I would suggest Mt. Airy, simply for the fact of seeing/experiencing the Nati Shop and the course before they close.
The only one of those courses I haven't played in the past month is Holler, but for the rest, they are in excellent condition. Also, Banklick and Idlewild will be in pristine condition this week as the Bluegrass Open is next Saturday. You can't really go wrong as they are all extraordinary courses. Enjoy yourself and soak in the Bluegrass!