2D TileMap with 3D Tiles (Path of exile like).

Hi,
First I'm just starting with Unity (2 weeks), sorry if my questions seems stupid ^^. Also I was not sure where to post so sorry if it's off topic.

I'm currently working on an rpg concept and for now I'm not realy sure a want to make a real game but it's good for the learning experience.

Today I did my first procedural dungeon generator and I'm happy with the result for now (yeah it's quite simple, just walls and ground).



Now I want to display this map in 3D using 3D tiles (like path of exile, see this video it's my inspiration:

).

I also want to be able to force spawn "prefab" rooms in my generated maps.

It's quite obvious I need to make an editor and a good tile system (tileAtlas with tile connections), but I was wondering if maybe some of you had some advices on the best way to implement this system in Unity.

I think I also need a way to optimize the result because for a big map that's a lot of gameobjects.

I looked for tutorials and documentation but I didn't find anything close to what I wanted to do.

Well, that's all, I'm looking for some advices, articles or artworks assets from the asset store I could use to test my system.