Nice hardscape. I would reconsider the ar mini though. In such a small tank I think they would detract from the aesthetic of it being a distant mountain scape. I think using Glosso or HC as a foreground is right on track, then maybe use a moss, such as Riccardia chamedryfolia, on the rocks to give the appearance of distant growth on the mountains. I wouldn't add anything larger than Glosso if you want the look of a distant mount range in such a small tank.
If you are set on adding ar mini, I would reconsider the hardscape, altering it to add more of an illusion of depth so putting ar mini in the front won't look out of place with the scale of the rest of the aquascape.
That's how I'd approach it anyways. Either way you're going to have a really attractive tank once you get it all planted. Keep us updated!