Just remove it, no need to wait, the new MTP is straight forward and intuitive.

I have never seen any other software where they keep the old menues/gui after they have launched an improvement to the gui when all the old functions are available in the new gui.

If one need to get used to it more why not take some time and make a small test project and set it up with the old picker and then do exactly the same with the new picker and take some notes to remember. As long as the old picker is available there is a risk one never moves over to the new MTP.