I guess you're not a fan of dirty (clinch) boxing.
I do agree that you can generally strike with more power when not controlling (when standing). However, there is a trade-off: by not controlling, you are not as safe. And, as I see it, the WCK method (fighting strategy) puts safety first (prevent his offense) -- something I don't see, btw, in most WCK "application demos" (which typically assumes your opponent will just let you hit him and not do anything in return).
Whether you seek out the clinch or find yourself there, you need a strategy and skill set for dealing with it. Control, and the fight for it, is a HUGE part of the clinch. In the clinch range, if you don't have control, your opponenent will. IME in the clinch, you can really only do three things: fight out of it (back to free-movement), control and strike, or control and take your opponent down. WCK provides a base method for doing all this. It certainly isn't exhaustive (neither is MT or greco or judo), but does provide a framework that can be useful in itself or used as a base to build from (which is what YKS did by incorporating some of Fung Sui Ching's weng chun into his method).
And I agree with your assessment about the ground, and I think GNP is a natural extension of a clinch-and-pound strategy.