60 is probably the limit for what you want. Any bigger and you have too much stuff. Don't forget, you aren't going to be away from civilization. You can always pick up stuff you need and send it home if you no longer need it, like gear for a special hike. Traveling and hiking are two different things. If you expect to be traveling by car or train, I'd look for a pack that has few straps or outside pockets to catch on things like latches.