re: Lathe Stand Modular Extension?

 I do not have one, but I consider the Tormek as more of a fine honing tool.  I would love to have one but from what I have read, one problem with the Tormek as your only sharpening tool is that it is rather slow when you want to reshape an edge and if you really get into turning, you will eventually need or want to reshape an edge.  That is true with other tools you might use it with as well.  If you want to fix or change the bevel of chisels or hand plane irons, you could be there a while if you do all of the work on the Tormek.  That said, you can do the main shaping using a coarse stone or diamond plate and then switch to the Torkmek for final honing and resharpening. 
Personally, I do not like hollow ground (honed) edges so I use either flat stones or a belt grinder/sharpener for most things.   My belt grinder is the Sorby Proedge which is designed for turning but can be used for chisels and plane irons as well.  Before I bought the Proedge, I used my belt sander the same way I now use the Proedge using some DIY jigs.  I keep thinking about getting a Worksharp 3000 but have managed to step away from the keyboard several times and later took it out of my shopping cart.  Horizontal bench space is an issue in my shop.