I have PS and PSITU both. Don’t have PS:IT major (that is still an option).
I know the difference between PS and PS:IT (and PSITU) is that PS has the “healing” scripting where the others don’t.
I love the speed at which PSITU seems to bring results. But I feel like I need the healing aspect also.
Been thinking of a custom ultima that will have PSITU. I guess my thought/question is, if I put Rebirth Ultima in the same custom, will that have the same flavor of “healing” as regular PS has?
"The Tao of Palpatine"
Build it like BILLionaire V3…
PS + PSITU in the same custom!
I thought about that, but figured THAT might be overkill 
I submitted this as a support ticket question also. Before @RVconsultant says to 
I’ll share whatever official response I get on this.
I came to regret getting PSITU, because it didn’t have a healing aspect. Later I added Regen. with it, hoping that would take care of my insecurities revolving around women. It didn’t help. It did help with overall healing.
But your question about having rebirth with PSITU will be interesting to find out. I suspect that Rebirth will more closely work with PSITU than Regen. did.
Why not listen to PS and PSITU? 
I’m trying to get as much magic done as I can with the smallest spell
If need be, I could put both into a custom. Just waiting on support answer to know how to move forward. I submitted it early today (Saturday) morning. So not expecting response until at least Tuesday
Adding RbU to PSITU would be half-assing it. One might as well make a PS-Core-Ultima.
Adding PS to PSITU would be PS getting its own Focused Ultima-tized Booster.
Or…
You can build PS + LibU to reduce the overkill; it would only be Jedi-level though, not Palpatine-level.
Or or or or
Just hear me out
PS + LibU + WANTED
The official answer from the support team:
"Hello,
Thank you for reaching out to us. Yes you can add Rebirth, the healing script is very similar. Rebirth seems to be one of our clients favorite titles. Try it out and let us know what you think!"