What about the barrel contour? Sporter, varmint or straight pipe?
The only thing you'll have to keep in mind is with the .270 neck you'll "have" to use the newer "blue box" brass. I just measured my older Lapua loaded brass and they come out at .268 to .2685. .272 "was" the go to neck chamber size for the older brass.
Something else to consider is the throat length on your new barrel. What bullets do you plan to shoot? 50s? 110s?
Best thing is to make up a "dummy round" with the bullet you plan to shoot, seated to the shoulder neck junction and jammed into the lands. That way you'll have lots of bullet/neck contact. The throat can only get longer. And it'll get longer sooner than you might expect
You can't shoot short and long bullets in the same throat length chamber and expect to have the same amount of bullet in the case neck.
Looks like you've pretty much covered it but think hard about the throat length before you jump on ordering your barrel. You want it to "your" specs.
I ended up with a "too long" throat and couldn't shoot the shorties with much bullet/neck contact. Fine for longer/ heavier bullets. Shorties were still accurate but not enough neck contact for my liking. Build it the way "you" want it.