The enemy ranges are not an oversight and I have had no intention of changing them. Changing mister behavior is impossible as a fix to long-range sniping; large enemies simply cannot go into the small places that you can.
In terms of the ranges being reduced by an unfun amount; that's hard to gauge. I'd be willing to increase the player ranges a bit, later tonight potentially if that's what folks want. By maybe 200px across the board if need be. But my feeling was that having to be closer to enemies will lead to more interesting combat.
In terms of enemy ranges that just means they can harass you from further away, which was always the goal. It doesn't give them any advantage when you are close to them. Their shots almost all move way slower than you do, and you move faster than all enemies still, so it's not like they have all the advantages. You have speed, they have range.