If you're going up, go big. Put a 200 amp service in. The cost difference is not that big. Part of the expense is you need a new feeder into your panel; from the weatherhead to the panel is going to need to be upgraded.

Another idea: Put in a manual transfer switch before the panel. If you ever decide to wire in a plug to feed the house with a generator, it'll be nice to have the transfer switch already there.