Hey there this tutorial I found very useful you might want to take a look at it. http://youtu.be/CVoFi2mnyhA
basically you need to make sure the adapt button is on for more organic models. You also are going to want to use the ZRemesher guides brush found in the brush menu and make a nicer layout. The video explains the edges around the mouth. You always want to keep an original copy of your sub tool that you are ZReMeshing using the duplicate button in sub tools. Then once ZReMeshed you can sub divide until your are close in geometry to your original sculpted model then hit Project all button in the sub tool project menus that way all of your sculpting and colors will be transferred to your new topology model. You should do this even if you are making topology with the Zsphere like you are. Project all will project any sub tools that have the eye on so if you have other sub tools besides the one you are building different topology for then you want to make sure they are off at the time of projecting.
you might also want to slide up the target mesh slider to a higher count to have better topology. Also for getting better poly or point count in the face, hands, feet of a model since they will need more than the rest of the body to have finer details placed on them try the use poly paint feature to paint the areas blue and the rest red or leave uncolored. I have found using a light blue helps with not putting too many points there. Use the slider there to change the color (for mine it is backwards lol for some reason) and then paint the lighter blue on the areas and then smooth with just RGB on and ZAdd off.
as far as the topology you have going here I would be careful with those areas that have squares like that ending in the middle of the arms and legs like that. You may end up with some problems I too have made topology like that in the past it has it’s problems. I would suggest trying to Change flows like that in the underneath part like the arm pit or in between the legs near the backside under the feet to hide it and sometimes you will need triangles but put them in places like that they are usually hidden then. The cool thing about ZReMesher is that it will only make square polygons. The fingers look fine though from what I can see.
I use this way of topology with the zsphere for joining two or more meshes and/or clothing now since the ZReMesher is truly fast.
Ps if you find ZReMesher taking way too long or freezes hit escape check the integrity of the mesh in the geometry menu if it has problems fix it if it still has problems use dyna mesh on a duplicated model go back out of dyna mesh, check it, fix it then try the ZReMesher again.
I hope this helps. Good luck and have fun
An example of the retopo (now the render looks a bit off because i just did a quick zbrush unwrap) but the normal map looks more or less fine
