From what I understand, the suit for Robocop 3 made in 1992-93 (a mere 5 years later)actually made improvements
Hm? Not in the slightest. RoboCop 3
went into pre-production almost immediately after RoboCop 2
wrapped, and because the budget was non-existent, Robert John Burke was crammed into the suits made for Weller. The problem was that Burke has a solid three or four inches over Weller, so he was packed into a suit that was already uncomfortable for the guy it was actually made for, and as a result it didn't fit him at all. You can see Burke's turtleneck through the neckpiece parts of the makeup (especially in the helmet-less makeup) and through the shoulder / elbow pieces, and you can see the sneakers he's wearing (instead of the bottom portion of the boots) when he gets blown off his feet by the grenade.
Some small improvements were made in the suit between RoboCop
and RoboCop 2
to increase Weller's comfort, and near the end of production on the first film they had cut the suit-on / suit-off time to something like an hour and a half, but ... yeah, no, the RoboCop 3
suit was not an example of improvements in any way, shape or form.