If Earth ascends to a higher plane of existence, where we will reside as advanced light beings, will our travels to other worlds throughout the universe all be locations within that higher plane, and not visible to us currently? Will we even visit worlds within the galaxies we physically observe as humans?

You will do both as you choose. There are worlds within worlds, universes within universes, in a sense, due to the differing planes of existence. There will be a whole set of higher vibrational worlds and galaxies in the new dimension you will ascend to, along with the Earth as a platform, but you are not restricted to that new plane of existence.