Can see the value in both centralized rules & local adaptations.
If you're expecting only locals will attend, don't see a problem with equipment limitations or allowances based on what people will be shooting, & what the targets can handle.
That said, really like that all Grand Prix have clearly defined (for the most part) parameters. If I'm traveling halfway across the country to attend one (& I will be), darn sure don't want to show up & find out my equipment is illegal, or can't possibly be competitive.
For me at least, it isn't about the money or prizes (ain't gonna cover my airline ticket, hotel room, & rental car

), just wanting to do as well as my abilities allow. If my talent & preparation equals last place, that's on me. I can either get better or accept that I stink.