From the ask 7 brewers, get 7 different answers department....
I basically agree with Jim... it can both enhance the flavors of the malt, and take them away!
Corn does two things, bumps perceived sweetness (maybe) and reduces malt flavor
In my experience, corn provides a subtle flavor, one that I think I can taste if you tell me corn is used, but I don't pick it out on it's own. I do not think corn adds the flavor of sweetness per se, but... to me, it does round out the flavor profile in my opinion. (I actually think it dries the beer out and helps the more subtle flavors of the malt "pop". In other words, I think it helps un-muddle the malt flavors from the residual sugars, letting the characteristics of the different malts... like Vienna and Pils, be more distinctive ) However, too much corn and the body of the beer gets thinner, and the flavors go "flat" again... so it is a balancing act...
I have substituted corn/rice/dextrose and table sugar in my "lagerish ales" (like cream ale and sometimes ale yeast fermented American Pils) and I find I can use Corn, rice and sugars interchangeably. A more experienced taster may be able to pick out corn...but I cannot.
Bottom line, I think you have a great base recipe for a CAP, and one that is simple enough, that you can play with different ingredients each time you brew it, and you can see what each ingredient does for YOU.
Enjoy!