But really, I see no real drawback to implementing this into PvE. I really cannot see how it would drastically simplify how a Job is played. It would just make the physical execution of combos slightly easier. And I guess it would force players who don't know what combos are to use them, haha. But even then I still think it should be optional.

I know I would use it in a heartbeat. I can get flustered sometimes and I cut combos, or my finger slips and I use the wrong move, or whatever. I get frustrated 'cause my fingers move faster or slower than my brain does. But it doesn't have to be like this! We don't all have expensive computer mice with a bunch of buttons, and I think this change would especially be welcome for controller users.