New Mixer and other gear

That is a big list and there are a couple of ways to go.  There are various "mixers" that include digital outs.  If you like the vs20 you should look at the vs 100, which lets you record more channels at once and includes a digital mixer, control surface etc.  there are also Roland effects included, although the reverb isn't much to write home about.  I had one here at home for review and it was a nice all-in-oner.  If the vs20 has a digital out you could use it w/ the digi in on the vs100.

Mackie and tascam make some low cost mixers that you can shunt digital tracks to your computer, as does Allen and Heath.  If that is what you are looking for.  If it is just a small mixer, A&H is the first I'd look at.  Soundcraft is another one (hey, I like brit mixers).  You can go to Sound on Sound and look for free at older reviews - they give good advice.

heaphone amp - I bought a presonus 4X for use here at home for $100.  Works great.  IF you don't need so much amperage you can pay about half of that, but I got it for when I was doing bands w/ drums.

Effects ....?  That is a separate thread and depends upon what you want.  Digi in is best if you can use it w/ your interface - saves on conversion.  Reverb or effects?  Etc.

A studio amp - for your monitors?  Depends upon them.  Again, you need to narrow down the question and specify.

good luck.

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