Adam, I tend to sound like a broken record on this so I apologize ahead of time, but the hunters at BOTW use the 7 rem mag a lot with 168 and 180 VLDs over either Retumbo, H1000, or 4831SC. These guys are building a lot of custom rifles
and shoot thousands of rounds. I've talked with several and they are nice people. I do not necessarily hold them as the "experts" but they certainly have a lot of experience. So, with all due respect, I tend to reference them.
John Burns, who used to be with them has started his own company, GreyBull Precision. They mostly use the 180 VLD if I recall. I think a 9 twist is preferred with the 180 where 9 to 9.5 is good for the 168.
I personally use the 168. Afterall, it's only a loss of 12 grains of bullet weight. Hardly enough to dwell on.
In terms of killing an elk at 1000 yards, Jeremy Winters killed one at 925 yards with a 6.5x284 with a 140 VLD. This hunt is on their Beyond Belief 2 video. That said, I think the 7mm 180 or 168 VLD will be more than adequate.