Drawing solid 2d maps and augmenting them in 3d is actually what brought me back to this site to start posting again. I like the idea of a game design section, but I haven't been on the forum long enough to understand if it makes sense with the community. I would definitely post in it as I mostly use Polycount for those type of posts right now, and while helpful, getting a different take here would be good to get some fresh ideas.

There is a lot of cartography in current video games and that sort of thing that definitely dovetails nicely with what the main point of the site is already about. From the complex bit of creating terrain based maps using World Machine, to simpler stuff to just adding height to 3d maps using normal mapping, basic 3d modeling, or tessellation. Though I guess that all does fit in the current 3d forum... I dunno. Tough for me to say, but if people in the community are interested I'd say do it. A lot of people that start creating maps and doing world building for home RPG campaigns end up in the video game industry as game or level designs so there is a definite overlap of skills there.

As for game engines, I'd recommend starting with Unreal and Unity. Both are free, well supported by very active dev communities, cross platform, and can produce amazing results if you work at it. Of course these engines aren't games in and of themselves, but both easily allow the creation of a 1st person camera to have someone walk through your level. In the end, that puts you well on the way of creating a portfolio and getting into the industry.