And while we're at it, given that Team17 has stopped making 2D Worms games on PC, why not try and get the Worms 2D series on GoG? There are still patches being made for Worms:Armageddon, but there is no way to buy this game anywhere...
Another great game series I'd love to see on GoG are the Zork ones... I believe they are owned by Activision, and the last one was Zork Grand Inquisitor, that came out about 10 years ago.
[Edit] Oh, and some older Monolith software titles would be great: Gruntz (a 2D top-view puzzle game with gooey gruntz) and the No One lives Forever series!

About bullfrog games, the next coming, from mucky foot (people from bullfrog), which was Startopia, was great, and sure would be a success there :P

Ah, I would love to see old warhammer games: Shadow of the Horned Rat, Dark Omen and 40k series: especcially chaos Gate.
Total Annihiliation with expansions would be great too.
Thans for Permieter: this game was highly ranked, but never legally avaible in polish stores.