Well the most widespread variant is the 3D stickers. Some of the 1983s and most of the 1984s were reissued in 1985 with a 3D sticker. There's a "free sticker!" graphic added on, suggesting it wasn't some clearance trick like taping a Minicon to the side of the box. There're 16 stickers in all, but seem to be random, and I seemed to get alot of the same 3 or 4 of them.
http://www.toyarchive.com/Gobots/Regular/Turbo.htmlThe closest TF analogy I can draw is the carded figures with Decoys but I haven't ventured far enough into G1 Land to see if they're differentiated. The RiD Combaticons have three variants that, from looking at the two Swindles, differ only by "X of 5" beside the name.
You got the running changes and "chase" figures (excluding the super rare Snoop, 43), but Scooter's a weird case. The 1983 GoBots have "die cast metal" printed across the bottom. The 1984s and 1985s replaced that with a solid colored bar that says "robots that turn into vehicles." Scooter, 27, is 3rd to last of the 1983 lineup (Pathfinder, 29, is the last). There are a couple sub-30s I've only ever seen on 1984-style cards, but I only have theories as to why.
Anyway...most of the 1983s that were reissued in 1984 and 1985 retained their original backer cards. That's how you get a Turbo with the 3-part graphic and a 3D sticker. The exceptions were the three running changes (BuggyMan, Blaster, Crasher) and...Scooter. Scooter was neither recolored nor remolded, so why they went and redrew him on a 1984 card is beyond me. Growing up, I had a few of the 1984 and that was all I saw on eBay for years; I've seen the 1983 all of three times and own one of them.
Finally, some of the larger GoBots that weren't Super GoBots came in at least two variations. Sears, and I think JC Penneys, sold them in plain mailer boxes, similar to how G1 Ratchet was sold in Japan. I've got both versions of ZOD. Command Center and Thruster show up on eBay occasionally and can be seen on Super Toy Archive. I vaguely recall this being true for the Power Warrior sets as well but don't have an example at hand.
Puzzler had three versions, a mailer box and two full-color boxes. The one looks like a water painting, kind of like the 1983 GoBots, while the other has a sharper and more dynamic pose. The duller one seems to be far more common and that's the art I see on all of the carded samples that show up as well.
I'm out of town this coming week but I could probably fill in half the GoBots listings once I got a light box set up...