Yes, anything is possible, but in this case, it is not probable.
Whatever star that would be signed would need ten times the wattage of NPH.
I don't think there is an actor (or actress) under 40 who can act, sing, dance, has the energy and discipline to play this 7-8 times a week AND is a genuine star. And also who wants to go out on the road.
A small regional production might work in Chi, SF and LA. However the production values would be substantially less than the current Broadway production.
Every time a piece of scenery moves there is an added stagehand expense.
"If my life weren't funny, it would just be true. And that would be unacceptable."
--Carrie Fisher