Always had a soft spot for Verona after reading the book years ago, but like you, I've never seen them have much success after promotion and usually become a proper yo-yo team. Obviously there's Juventus to contend with, as well as the Milan teams, but they often drop off quite dramatically so the main competition in the long term is Juve.
Nurnberg are also intriguing, after all their historical success, and Bayern are a juggernaut so they're always going to be challenging. I think for longevity's sake, Nurnberg would be the better option, simply because I think Bayern are better than Juventus, and there's also a whole load of other teams capable of gunning for the top spots - Dortmund, Gladbach, Schalke, Wolfsburg etc., so there's constant competition amongst the big teams. Plus, the money in Germany is great.
I'd also like to suggest Kaiserslautern if you're thinking of Germany. Another historically successful club fallen on hard times, plus they won the league straight after promotion in 97/98.
Or, if you use a data update, 1860 Munich are down in the 3. Bundesliga.