OK, here is my proposal, based partly on the system in the state I grew up in, and partly on the belief that the current SC system is divided into groups too small. If you stay with me, I'll get to how it addresses the original topic. Root cause: too many regions and too many school size divisions creates a regular season that doesn't have any flexibility resulting in unfair pairings and qualifications. Schools have such little freedom/control over who they play.in the games that "count". We have regions with only 5 teams, and 4 of them make the state playoffs. And that 4th team, with a losing regional record, might even be a top 10 team in the state and make the second or third round of state playoffs, but we already know they aren't winning it all. Meanwhile, teams in some uneven regions with "advantaged" programs and only 1 or 2 playoff slots have no legitimate chance of making the playoffs, while those in others are practically guaranteed to. My proposal:

-Reduce the school size divisions from 5 to 4. Least critical part of proposal, but feel sliced too thin now. Any team can request to "play up". Allow teams/schools within some % of size cut-offs to apply to move up/down to balance a particular region or for specific circumstances. Mechanics for determining size division are probably not much different than now, just one less.
-Reduce the number of regions in the state to 4. This will put about 16-20 schools in each region at each size division.
-Instead of requiring a full regional regular season, institute regional play-offs. Top 2-4 teams from regional playoffs qualify for the state playoffs, depending on how big we want the state playoffs to be (8 teams, 12, 16?). Can be distributed evenly between districts, or weighted if regions aren't "even" on a sport by sport basis. With only 4 regions, probably evenly. In additional to regional champs, regions can have a meaningful consolation game to determine entry/placement in state playoffs.

To qualify for regional playoffs (regions could adjust terms to some level based on region/sport), teams have to:

-have a winning record OR one of the top 8-12 records (depending on size of regions/sport/etc) in the region. Can incorporate first round BYES to deal with fluctuating number of qualifying teams year to year.
-Play at least 50% of games against teams in same school size rating or bigger, and not more than 30% against schools from a smaller size ratings. Schools can push themselves against higher competition, but not to the point they play up and essentially "drop down" for playoffs.
-Play some % of games (50% maybe) against teams within the region (no size restriction). This combined with above size requirements will mean a team is playing a meaningful number of games against relevant competition.
-Regional administrators can waive above requirements for situations like uncontrollable hardships (games cancelled due to weather, illness, etc.)

How does this address the issue at hand? Teams have freedom to schedule whoever they want. Schools can schedule "independently" or groups of schools can form 4-8 team leagues if they want. The leagues can cross regional and school size boundaries, and schools can still qualify for their regional playoffs. Schools can try to game the system and schedule only cupcakes, but all that gets them is a first or second round beat down in the regional playoff. It doesn't knock anybody else out of the same opportunity. A team in a stacked area or league can still earn there way to regional playoffs because out of size division/region games aren't meaningless. Both the teams I described in the original paragraph can get in the district playoff and see how far they can go. Teams have more flexibility in who they schedule to have meaningful and competitive regular season. Regular season maintains more meaning for more teams through potential HS leagues and Regional qualification/rankings. With more flexible scheduling, teams near regional boundaries aren't penalized compared to those more centrally located.