I am truly curious about this. For the time being let us set aside the fact that it was first used successfully this way and that it is historically correct.
The questions to be answered that I see now are:
1. Are there adverse chemical reactions when using a substitute ether solvent?
2. Are there mechanical/substance related problems/issues when using an ether substitute solvent?
3. Are there timing issues when using an ether substitute? This may be a subset of the question above.
Diethyl ether evaporates extremely quickly thereby lessening the film formation and toughening time which is a bonus for any "hand" operation. However, this quickness works against us by giving a short exposure/developing window.
Collodion is essentially nitrocellulose lacquer. I mix/create solvent blends for use in lacquer work for art conservation treatments to give needed working characteristics. Can some of them work for us in wet plate collodion photography?
Collodion is soluble in amyl acetate, some of the alcohols and it should be soluble in "lacquer solvent" which can be many things depending upon air temperature and whether it is for spraying or brushing.
The question of miscibility of the various potential solvents is the first problem to be investigated followed by the effect on the rest of the wet plate process.
I haven't tried any of this yet and won't be able to for a while until my traditional supplies all arrive. However, a good experiment begins with the research into what has been already done and the results of this work, good, bad and indifferent. Please share your experiences or your expectations.
Why am I curious about this question? Well, that is the way I am and I think that without such curiosity those first successful wet plate chemist/experimenters would not have been successful. I will try a fully traditional wet plate technique but being able to use more readily obtainable materials may be of more increasing need in this over regulated world.