3. 60 feet max range severely limits the advantage of getting to high ground and making use of angles and cover
This is a good point, and no "you can jump/disengage" is not a defense. It's probably not feasible to put the full range in the game, but perhaps the range of bows, Firebolt, and Eldritch Blast should be increased to 80 feet, so you can't have enemies move + dash to get into AoO range of casters.
