[Peter Ebbesen]

With the caveat that I have never, ever, tried playing Sauromatia, I do not see how S1 can be considered useless for other purposes than communion so long as the commander chassis is not prohibitively expensive for spamming purposes. All it takes is a single Banner of the Northern Star (or the spell itself, though S1s cannot cast or forge them natively) to turn a bunch of S1 mages into S2s. That's not bad.

As for communion, you don't need the witch kings to make sensible communions - S1 mages are perfectly capable of bootstrapping themselves. Using some of them as masters and some as slaves in their own private communion and have a master cast Power of the Spheres (as well as the Northern Light from spell or banner) and the other usual defensive astral spells, turns a host of S1s into a strong battery of soulslaying astral mages. While it certainly is not the best thing since sliced bread, it definitely has its uses.

Whether any of these two options are really useful for Sauromatia - you tell me. As stated, I have not played them, so there might be reasons not use them, but at least they are options that any nation with recruitable S1 astral mages should keep in mind, even if they end up dismissing them for practical purposes.