Dear Batcat,
I like the material for the orange tiles, however the rest seem to have overkill normalmap, and the grass looks like a sort of organic material that resembles creep from StarCraft2, that slimy unstable soil.
What I would suggest is the following:

On the grass, try to have linear normal with even distribution, or grass patches with even distribution.
Linear grass: https://www.filterforge.com/filters/813-normal.jpg
Grass patches: http://4.bp.blogspot.com/-tBYrf_WA5cM/Td41JPb1oXI/AAAAAAAAAHQ/i5gxo77vp9A/w1200-h630-p-k-no-nu/forest_grass01.png

For the colored tiles, I would personally tone down the bump intensity, or made it with less noise. There is another option, there are many anti-slip tiles that feature a motif, such as flowers, or waves, or some sort of other figure which acts as the anti-slip.

The "tree", I am not sure what sort of material it is representing, it reminds me of external insulation coating of houses: http://www.artdomconstruction.co.uk/images/house-thermal-insulation-london1.jpg
Thus I am not able to comment on that.

Please take the above comments as constructive criticism, as I have pointed out the steps to make them look different. Also please note that the above is solely my opinion and does not reflect the ways it should or should not be done, as that is very much subjective.

Thank you very much for your attention, and happy texturing!
Papi

I agree with the overkill normalmaps. I stumbled across a website that made it easy to create normalmaps and allowed you to manually alter them and such. After this discovery I went a bit over-the-top with it now that I had found this great tool. I have updated the texture and now the tiles are less bumped. The motif idea is neat so I will keep that in mind.

The tree in the middle is made of the tiles, it gives off a bit of a minecraft-y look but that's ok for now.

Thanks for liking the tiles!

The grass texture is what I'm the most concerned about since creating grass isn't as easy as the other ones, I know it looks too slimy and Ill probably work on it more before do anything serious with it.

Thank you for your comment!

In case you would like to make your own normal maps, there is another way than using tools such as gimp or crazybump. You may want to look into modeling the actual asset in blender, and baking normals onto a texture, then you can use it as a normal map. For example, at grass, what you can do, is make a grassy plane in blender with the particle system, have a camera positioned above in ortographic mode, and then render the normal pass. After that you can tile the texture and you have a normal map for grass. It is kind of a more extreme option, but it does work a lot of times when props are being made.

Of course most of the time the best is to photograph your own textures, then run it through crazybump :P