I'm sure you can see the same problems I see - you've got a faint line running through all the boards along the edges of the tile, and some of your boards are never-ending.
Do you have any sprites that would be used for this project? The boards are rather dark, so sprites that are mostly dark or employ a lot of dark outlines might not read well. In addition, despite them being so dark, there might still be readability issues because the dark outlines are fairly prominent. Consider perhaps getting rid of the darkest colour or making it lighter and using it more sparingly, e.g.
(I also modified the colours to add a little hue-shifting, the colours get progressively more purple the darker they are, this makes them feel a bit more interesting without introducing too much contrast.)
What size is this tile meant to be? I made a 24x24 one for my example, but because yours was shown in isolation and apparently with an outline, it seems to be some other size?