When Stardock stared using Steam to distribute your game software, i believe the reasons you stated had to do with lower Stardock costs related to publishing game patches and lower costs for early access type beta testing. It occurs to me that for your older games that are now stable (for example Galactic Civ 2 and Legendary Heroes) an additional outlet might add to Stardocks earnings. If Stardock were to start publishing its older games on GOG.com in addition to offering them on Steam might you not reach a broader potential market? Of course the newer, higher maintance, games would continue to be sold on Steam only.
Does this make sense to you?