Thanks!
...not to sound proud, but is there a problem with my tileset?
If there's a reason that Mike's is better, I want to know so I can step it up. = P
Lol good question, it's annoying sometimes when people don't give any
constructive criticism.
Your set is far too dark for thing. It's got the "quake look", as I call it, which is a common problem when people do stuff like this. Basically the contrasts are too soft and over use of brownish colours leads to everything looking smudged and dark. Another part of that is the detail of the tiles, which are very nice in themselves, when combined with the colour scheme and fine detail level it reduces it to a blur once in game.
A good example of this is the remains/bone/gore tile. It's a great looking tile, but in game the "pile of bones" at the bottom kind of just becomes a bunch of squiggles and the skull loses definition, as it lacks contrast and the detail is too fine for the scale.
In comparison, mike's tile for the same function is a caricature style skull with a single bone, which stands out and has instant recognisability. Mike's style in general is a little caricature with the "big headed" dwarfs which adds to the usability, but doesn't necessarily make it "better" looking sprite, but more accessible.
The font is possibly a little love or hate. I love it except for the aforementioned brownness, but I'm sure a lot of people would be turned off by it's lack of uniformity and generally being a little unusual.
18x18 is also an unusual size which may put off people simply becasue it's not the norm and takes a little getting used to. I quite like it as a size as it offers slightly more space on tile but for very little sacrifice in terms of viewable screen space. But then again it makes a pain to mod or adjust with other tilesets as it is not the same scale.
Another point is that it can be difficult to tell the difference between same colour but difference material tiles, orthoclase looks very similar to gold and is tricky to tell the difference at a glance. I'm sure you can tell the difference and I could too with practice but at first it's confusing and a little annoying. Have in mind as well that people will be coming from using ascii, mike's, phoebus's(spelling?), or another popular set where things are much more readable and but less pretty.
You would also get more downloads if you set was a little more visible. People don't go to creative projects to look for a tileset they look on the mods forum, the wiki or google for DF tileset, I don't think any of those 3 would lead to your set. Mike's is top result for "dwarf fortress tileset" on google so you have a uphill struggle to be more popular than his
That said I really like what your doing and some of the tiles are really great, ground tiles and the chubby dwarfs in particular look really good in my opinion.
Longer post than I expected but I hope it helps.