Balls are a great beginner snake. I'm basically a beginner myself with only about 6 months experience, and if you only get one ball, you'll want another snake soon enough. However, if you're set on keeping the tank you currently own, have you considered another reptile? Personally, I'm interested in ANY herp, all though right now I only own snakes. Why not look into a herp comfortable with that much room, or maybe a species of a larger size. I think someone mentioned heat/humidity. I owned a 55 gallon tank for a short time with a divider. Heat wasn't too much of a problem with the right lamp, but humidity was a HUGE pain. If you can find a herp that is comfortable with a lower humidity and tolerant of the occasional husbandry mistake, I say go for it! A couple Beardies may be great candidates (though what I know of beardies is pretty limited!). Breeders aren't handled much, but I held a male once who was a DREAM!

At any rate, I liked my tank set up for my ball, but when I realized it wasn't the best for him I switched to a tub. Don't be surprised if you end up getting rid of that tank to make your pet's habitat perfect.