What in the world are you talking about?
If you want to go featureless, you can't have a pistol grip. Not everyone wants a grip wrap, not everyone wants a hammerhead. Using a large capacity magazine is not the only reason. I don't care what sort of tool you have, riveted glove, gpik, ubbt, etc. I can still change my magazines faster by just hitting the button. I don't have a tool to get lost, I don't have to rely on specific magazines(if that's what your tool is).
What do you mean by 2 dollar PG cap? Putting a cap on the pistol grip so you can stick something in it doesn't make it featureless, nor is leaving a tool in there for a bullet button faster than just hitting the mag release.