Number of tag providers

I am creating four different vision projects onto an existing gateway which already has a project from which I am essentially going to be copying to use for the four new ones. There are actually already two other projects currently on this gateway and those two have a ton of similarities. The programmer who did these two did say if she had to do them over again she would have done things differently to make things easier.

I am struggling with the best way to set these next four up. I am going to create a new tag provider for sure but should I set up one new one and put all four new “cells” within that one tag provider or create four new tag providers (one for each “cell” or project) and then this way I won’t have to use indirect addressing because each cell or project will have its own tag provider? The UDT’s being used between all four will be the same. If I went with one new provider and incorporated the “cell” to create/edit each object I will have to go through every single screen and change the tags used throughout to indirect.

Can indirect tag addressing be used within transaction groups?

The global project right now is empty. Would it make sense to put as make as I can within this global project and then be able to use them for the rest of these four cells?