I'm with out of stater on this one. I like a 100 yard zero. Several reasons why but the post isn't about that. The 1000 yard game isn't one for shortcuts, gimmicks or half azzed equipment. Your on the right track and asking questions is how you find these things out. Chances are you'll need need a 20moa base, most scopes won't get you to a 1000 yards. A 300WSM takes 25 or 26 minutes, a 6BR is close to 30 minutes, most everything else you would use in competition will fall between those numbers. Getting a scope to go from a 100 or 200 yard zero to a 1000 yards is highly doubtful.
100 yard zero vs 200 has proven to be no benefit to me, I know a lot of guys that like 200 zeros but I'm not one of them. 100 yard zero shoots @2" low at 200 and 9" low at 300, both super easy hold overs chucks and deer. 400 and 500 are 25" and 45" respectively. One could argue hold over at 400 but no way at 500. Besides I have no issue with reaching up and putting the clicks in, quick, easy and accurate.
You must also keep in mind there is a huge difference in holding off in a match situation to hunting situations, I'd be happy to share my experiences with those differences too