I've always wanted to game this battle, and I've given the scenario a fair bit of thought. I got hooked playing the SPI game.
A Union victory requires the Confederate force to be so badly torn up that it is obliged to retire back into Arkansas, leaving Lyons the saviour of Union leaning Springfield.
I would have the CSA force commander deploy his army however he likes so long as there are a minimum number of Brigades encamped east vs west of Wilson's Creek and north versus south of Schuyler Creek. All CSA units are encamped and must form before they can do anything. The CSA cp must be near the confluence of Schuyler Creek and Wilson's Creek.
The Union commander may split his Brigades as he pleases and may enter at the 3 historic places, plus straight down Telegraph Road.
For the Union to win, they have to hit the outlying Brigades hard enough to roll them into adjacent unformed units, in hopes of generating a cascade collapse. Obviously, they can't disperse too much or lack the strength to overrun a section. Obviously if they hyper concentrate, they will leave the Confederates with too large a force unfought. The real trick for the Union is finding a way to carry their attack across either of the creeks to continue their attack or effect a link up.
Special rules:. The CSA cp should be especially hard to activate. As it happened, the site they chose was in an acoustic shadow. They could not hear anything, even cannon fire, coming from the action to their north.
Any gray clad (either side) unit may opt to have or forego a unit color. If they have one their unit gains cohesion, but are readily identifiable on the field. If they opt to pass on a color, they run the risk their companies may get separated, but they gain the benefit that enemy troops may mistake them for friendlies.
Both CSA units have to be equally hobbled. McCulloch and Price had little use for one another. If you cripple McCulloch but leave Price intact, he'd press on even if he had to do it alone. If McCulloch smelled blood he'd scrape off a crippled Price, as far as Springfield, but likely no farther. Never,ever, torque off a Texas Ranger.
Just some notions.