Eddie,
If you read the rest of my post (on my forum), you'll read that (most) ether has a stabilizer in it and that alcohol helps stabilize it even more (preventing it from forming peroxides).
Remember, Collodion already has a substantial amount of ether in it. I'm with JG on this; the "peroxide danger" is usually overstated. It's something to be concerned with, but there are other chemicals in the process that are far more worrisome in my mind. I think we spend too much time talking about it. The solution is to mix up PART A and then mix with PART B as you need salted Collodion. PART A will keep for a very, very long time, no marbles, and no catastrophes. It's how Kodak sold it in the 1930s - $4 USD per gallon. Your "salts" came separate. It's always good to store your chemistry in a cool, dark place away from ignition sources, children and animals.
Marbles: Are you talking about wet plate developer, or something else? FWIW, you don't need marbles in wet plate Collodion developer. It will stay good forever.
Tinyfailures,
Solvents do a couple of different things in the process. Ether plays a role in adhesion (to the plate) and the "toughness" of the "emulsion" (make a batch of all alcohol Collodion and drag a wet cotton ball over it, you'll know what I mean).
Also, this particular formula is ready to use shortly after you mix it (NH4I used, not KI), no clearing, and no waiting, ready to go. However, like all Collodion, it does get better with time. It works great for both positives and negatives too. And it lasts for a very, very long time.