Tileset, by 
User Friendliness 1/1: It’s a very small tileset, so there’s not much you could miss when actually using it.
Overall look 1/6: It’s just another MS Paint tileset to me. Use a proper program next time like Paint Shop Pro or Photoshop (or whatever the guides suggest). The colors used in the textured background need to be placed in the right rows of the tileset palette in order for them to not get the messy white color (see JCSref and the othersites to understand this).
Usefulness 0/1 It doesn’t have all the basic tiles needed in a tileset. There are a few eyecandy tiles, but not enough to give a level variety in scenery.
Size 0/1: Make it bigger in the future.
Originality 1/1: Yeah, it’s original. That’s about it.
Overall coolness 0/1: If this tileset was properly drawn and featured the sort of scenery you would see in the Andes (jungles, mountains, plains, etc), this would be a great tileset, but I think you need to put a LOT more work into your tilesets if you attempt to make another. Make a checklist and be thorough when you make a tileset. It should have:
Ground (all angles and corners that anyone could possibly need)
Tunnel (indoor areas where you use layer 5 scenery)
Vine
Hurt (spikes, etc)
V and H poles
Buttstomp and Destruct Scenery
Animations
Signs (exit, bonus, and text)
Directional Arrows
Hook
Collapsing Scenery
Teleport
Disappearing Ground (invisible tiles with a mask that allow people to make secret paths or drop enemies/items from above)
Extra Scenery (foreground abd background extras; any kind of eyecandy you can think of — add as much as possible).
Now go and make a better tileset :)
