In many ways the limitations of the map editor for the original Brood War made the maps much better because you had a set of specific tools to work with and confines to work around instead of a vague set of development tools which would only be useful in the hands of someone already educated and presumably employed in the game industry.
The total absence of that level of micro in SC2 is a large problem with the game ('A-Move' strategies work quite well), though it does serve to make the campaign easier.
Pathfinding was bad over long distances but this placed much greater emphasis on the micromanagement abilities of the player and thus greatly enhanced the competitive scene. By which I mean, they sorta had it figured out by the time the genre was dying around Warcraft 3 era. It took RTS games in general too long to get pathfinding right. Doesn't helped that the default ramps in the game are like, 2-3 units word, further creating dumb chokepoints leading to giant conga lines. Pathfinding in Starcraft 1 is fucking atrocious, leading to all your units just single file marching everywhere unless you babysit them constantly.