As I explained, I did it all in multiuser mode. /home is simple, it's the var and stuff that would require single.
I don't need terabates in / it's just that it is a single partition - everything is under / except for /home (Redhat's weird partitioning scheme). Thus if I need 3TB in /var, I need to expand / to that size.
The other option I could have engaged is gparted, I've used it before and it's pretty good at shrinking / resizing partitions.
But in my case, deleting completely and recreating was safer. I am just kind of mildly irritated by lack of critical thinking and being proactive. Who needs 98% of space in the /home partition? On a production machine? That's what I always pick my own sizes, the one time that I don't, I have regrets.
I mean RHEL is a OS for production enterprise grade data centers, it is a very poor choice for a personal machine unless just must have it. What system layout would work in a data center? With storage perhaps measured in Terabytes if not Petabytes? Perhaps a bit different than a personal Buntu box with 500GB SSD.