I see that the new Battletech game is about to hit GOG. Just a thought would there ever be a chance of the older games coming to GOG like Mechcommander or games like ghostbear legacy?

Depends on the legal status of a game, license etc., and the willingness of gog to acquire the rights of selling these games. Or of any third party publisher wanting to do business with gog.

As with most old games they are usually in a legal hell, as in no one knows who holds the license of the game or even worse if their are more then one holder, which makes more or less impossible the sell these games. But sometime things do change and the rights will be acquired by a third party and then they approach gog to sell it here, which happens with System Shock 2 a few years ago.

So the best thing is to vote for any game you are interested in on the community wishlist and hope.