While I would love for field moves that are usable outside of battle to return, I think some of those moves would be better off as key items (particularly Cut, Surf, and Flash especially). I sure wasn't happy that S/M no longer allows field moves, even Dig (which, although was never an HM, was an excellent substitute for Escape Ropes).
Having HMs around, though does require players to strategically plan their Pokémon teams throughout the time they go through the game's storyline, something that I've always done by boxing earlier Pokémon and replacing them with others along the way. Though I will say, I was not all that impressed with there being so many Water HMs (particularly in OR/AS).