You have to keep in mind that they're building a common model for both the 2-rail and 3-rail markets, so you're going to see some compromises. Even as a mostly (some would argue former) 3-rail operator, I don't think the wheel treads need to be as wide as they are on the 3-rail version, but I don't use "round-top" tubular track.
I have several 2-rail versions of MTH locomotives going back to my first set purchased in 2009. I've thought about moving the side frames, but it requires a high level of precision since the MTH side frames include the brake shoes which just barely clear the scale wheels. I like the addition of a better looking train line hose and MU cables and might do that to mine.