My top favourite would have to be Fluorite Plains. Fluorite always has people there, it's the best place to find roleplay groups with semi-lit to literate players. It's where all my friends seem to be and the most busiest map in Feralheart.
SkysRim: I love how SkysRim is up in the sky, how there are just floating islands with trees, waterfalls and grass. It's quite peaceful and just a beautiful map
If the route to SkysRim were quicker than I would probably be there all the time.
Temple of Dreams: Again, another lovely and peaceful map I love to visit. I like the way the whole map was built, ramps and rings and a large platform at the top. Flowers and waterfalls just make the place look more serene <3
Ficho Tunnel: I really love how quiet and dark this map is (especially if you have Mink's Darkness Mod). The large pool with a crystal in it adds an eerie glow to the small area which I personally love. As you wander further into the cave you can hear the sound of a waterfall nearby then there's a little flower covered slope.
I don't download many maps but I personally love dark forest maps with a realistic environment, running rivers and waterfalls, shrubs and narrow paths. I also love city maps and even those "Escape" maps where you rp as something trying to escape the area.