There was a DRM free patch released for DKS a little over a year ago. Though waiting for a GOG release did mean you got the Developer's Cut version (retail versions of D2:ED/DKS, digital versions of FoV and some digital releases of D2:ED/DKS could be upgraded to D2:DC).
Neither Dragon Commander or Original Sin have been released yet. The first should be out about May/June of next year, while the second will possibly be released by Q2, probbably by Q3. Those are the current estimates, anyway.
The main character in DC is a dragon knight, and the game is set in the time of Maxos. It started off playing around with the dragon combat in DKS, for possible DLC, but then they had to add missions for something to do, which were boring unless there were choices and consequences, etc, which evolved into a full game (and was moved to their new engine built for Original Sin, rather than continue with the modified Gamebro engine used for DKS). Dragon Commander is a real time strategy game (with
land, sea and air units, where you can direct your units or join in as a dragon... specifically, a dragon with a jetpack). Each round starts with an RPG section on your base ship, where you talk to advisors, make various decisions (more than in any of Larian's previous games) about policy and research, etc. Setup for combat is on a turn based strategy map, where you distribute troops, etc and decide which battle to participate in yourself. This stage was prototyped as an actual tabletop strategy game, and refined until it was good enough that arguments broke out while they were playing; the collector's edition of DC will include a
physical boardgame.
Original Sin is an isometric RPG with turn based combat set before the events of Divine Divinity. There are two main characters, and the game can be played in co-op mode, where both main characters can participate in conversations; disagreements are resolved based on stats (in single player you can set a personality type for one character to make responses based on, or set it to random). The game will ship with an editor. See
Divinity – Original Sin revealed and other blog posts for more information. Also check out the
Larian Studios YouTube Channel for videos of both games, though the design of DC has evolved a bit since the E3 presentation, and additional work done in D:OS with graphics and lighting, etc.