I wouldn't change a thing. And you know how some CL recipes say the yield is 18 muffins but you are lucky to get 16? This one is a full 18 muffins. Taking some to a meeting at the office tomorrow and get to keep some at home for the minions. Win/win.
Very tasty, but did need some modifications. The streusel is kind of dry and doesn't stick to the muffin top, so I would suggest putting half of the streusel in the mixture and the rest on top. Also, it yielded 13 muffins for me. I'll definitely make them again with these changes.