String guage, action/setup, and string types are one of the subjects which never end in the realm of debate. I am very glad that you have contacted the Luthier as that person can offer an intimate insight and perspective.

You have received a lot of answers but I feel that we need to know a little more to offer good guidance. To offer an informed answer I would also want to know what styles of music you play, when the guitar was built and by whom, is it a straight neck or a relieved neck (plus how much relief), what type of setup you think you prefer, when was the last time the instrument was professionally setup.

I am guessing that you and many people that are pondering this issue are unaware of the variables and the questions which need to be answered to get to a useful answer. Many players play what they play and it does occur to them that some players do things very differently.

The answer I would give for a pre-WW1 parlor guitar primarily used for finger style is completel;y different than the answer I would give for WW2 vintage Gibson L5 which was used for playing Big Band Jazz.

The action and string gauges typically preferred by bottle neck players are usually very different from what most fingerstyle players would prefer.

-E