I mean, their +1 would stack. Crit range expansion was a big part of the game in 3.x. That game had you crit confirmation, and 5e makes it easy to get advantage, but I literally do not care.

Champion is also a badly designed class, it could have had maneuvers for a teensy bit of complexity, but they needed a "newb" subclass, paving the way for conceptually elemental subclasses with no mechanical complexity at all (note that the wizard didn't get hit with any of this).