I like what I see; neat hex iso tiles! But, one thing about the water that definitely loses some merit is that the fluxing underwater animation is extremely mechanical, obviously done with posterized hue shift tweens, or something similar. And what that does is achieve a neat precise effect, but it's so mathematical/machine lookin', it loses out on that artistic organic manually drawn quality. I really like rikfuzz's underwater texturing, but now let's see him animate it like you, hehe. That's a whole other matter. You could try a looping bitmap displacement effect if you're photoshopping, but then it has to tile as well, so not sure how that'd turn out.
Nodoby seems to like the falling water texture on the water tile sides, eh? It's not too bad. I do agree less contrast would be good. No need to draw much attention to it. There is a discrepancy here however, and perhaps I just don't understand how these will be implemented in your game or whatever they're for, but you're treating the sides of the grass tiles as cross-section, like they're sliced, exposing the side (if not seems little blades and details should be hanging down over the soil layers rather than a perfect edge, but I guess this could boil down to a style choice), yet then you've got your water tiles like they're not sliced, but rather water cascading over an extruded hexagonal shape. I say make the concept for your tiles consistent to reduce confusion.
Not liking the grass top-face's texturing. Too sandy, it doesn't describe anything, it's just noise. Left/right sides of grass tiles are banded, must not be done yet. The little plants need help.