I have similar situation: I have 3G hd on my PC and >80G hd on my Amiga. Only use for the PC is the DC(++), so I've shared Amiga's files on it. I tried couple of ways (samba, nfs..), but then I found that it seems to be easiest and most stable to mount my Amiga's ftp as a drive on Windows. I found Internet Neighborhood by KnoWare, which can do the job. So, that and ftpd on Amiga should be fine, if you don't figure out any better way to do it

Only negative thing with that is, that when you start the DC, it takes quite while to do the filelisting over the ftp. But otherwise transfer speeds etc are good.