I am just collecting parts as well. I have a 5.7 core, 6.4 cam, 6.4 intake, Holley pan, mounts, headers and a T56 Magnum swap kit from SST. I am sticking with the TB suspension as it is well on the way to being pretty well sorted and I see no reason to change directions.
Truthfully, I'm not building it exclusively for a road trip. I live 30 miles from the "big" city on a 2 lane 60 mph highway and it just makes no sense to me to build anything else. Currently the 360/A833OD/3.21 combo works fine and I am sure it would do the job if I need to make a road trip with it.
I do need to do the Ram AC box swap like in the link above though. Later on in the summer AC would be really nice and almost a necessity for a road trip if I wanted to bring my wife.