Typically a well-designed bike will have geometry that matches wheelbase to head-angle, fork-rake and trail for balanced handling. In practical terms, wheelbase will make no difference in overnight touring experience. Wheelbase just determines how tight of a circle you can ride at low-speed, like making a U-turn on the sidewalk. In that regard, the twitchiness/steering-response you feel when riding has more to do with head-angle and fork-rake.

For touring, you'll want a more relaxed head-angle with lots trail for stability. That really makes the miles more comfortable as you don't have to work at keeping the bike going straight. That gets tiring on long rides.