I posted a bit ago but it apparently did not show up. My apologies if I have two similar posts.
Speaking not from any personal preference, I can tell you the defacto standard backline rental kit for "run and gun" festivals (everyone shares a kit) in the rock, pop, country or similar genres would be a 22-10-12-14-16. The 14 and 16 would be floor toms with legs. Drummers choose which toms they want to use with 12-16 or 12-14-16 as the most popular configurations. Regardless you can do a 1 up and 1 down, 2 up and 1 down, 1 up and 2 down, and of course, a 2 up and 2 down configuration.
You might opt for a 13 instead of a 10. A 22" is a versatile bass drum that will cover almost anything except the be-bop stuff. If you actually expected some light combo jazz then perhaps a 20" would be in order. You can still rock on a 20" but it is tough to be-bop authentically on a 22". To be honest, there are a lot of drummers that will struggle with 24" or larger kicks. I have found that drummers that play larger drums will acclimate a lot quicker to smaller kits than the other way around.
Keep a few snares available. In a perfect world a 5/5.5 and a 6.5 in both metal and wood. Of course, a Supra is a nice Swiss Army knife. Also a double pedal is a good idea. (Sorry Mike T). In these situations you have to be able to set up and run quickly. To that point, you want to consider your tom mounting hardware as it may be adjusted or completely re-worked multiple times a night, a task that a lot of vintage hardware is not at all up to.
By the way, for those of you who might be OCD like me, you might be cringing at the thought of moving mounted toms from left to right with regards to the placement of head logos. Instead of orienting the head logo to the badge, I align it with the tom mount. While the logos may be crooked, they will always be crooked symetrical and at least they never end up upside down.