the grid isnt the floor. because ESF models are scaled, your char will be floating in the air by an admirable amount. to counter this you'll need to move all your base animations down by somthing like 2.5 off the top of my head, the best plan is to decompile one of the origional esf models and measure the Y distance in an animation, that way you'll get the precise distance to the ground.
Also, to make it easy on yourself, just save an idle single frame animation with the new "floor" and work your new animations from there, that'll save you realigning it each time. personally i just add the scale/move command in the QC file, but its a bit late to do somthing like that now ;3