Satsuki, the Living Lore looks somewhat interesting as a saga tribal commander. Getting the later verses of
Elspeth Conquers Death or
The Mending of Dominaria at turn early could definitely have a significant impact. That said, I'm not convinced that there are enough sagas to support a full deck, at least in two colors. There also aren't a ton of inherent synergies between all the different sagas. I suppose that the Kamigawa sagas flipping into creatures (and the overall enchantment theme in GW) means that there a bunch of additional support, at least. Probably still a little too narrow to justify running over a normal enchantress commander, but something to keep an eye on as more sagas are printed.
Heiko Yamazaki, the General doesn't appear to be linked mechanically to
Brothers Yamazaki, but I'll give it a pass. I assume their sibling will be mechanically linked in some way. Either way, mono-red artifact recursion yields an immediate comparison to
Daretti, Scrap Savant. Heiko doesn't look to be as powerful (as one would expect from a common), but looping
Conjurer's Bauble or another utility artifact every turn could be amusing.
Raiyuu, Storm's Edge looks like a strong support card for NEO's 'whenever a warrior / samurai attacks alone' theme. At the very least, it does a decent
Rafiq of the Many impression. No exalted means you miss out on the +1/+1 pump, but Boros has more combat synergies anyway. Personally, I'm more interested because it gives relevance to
Samut, Voice of Dissent being a warrior - changing Samut from a 4-turn clock to a 2-turn one is a significant speedup. (
Aurelia, the Warleader is still the best instance of this effect though, outside a specific exalted-ish build)
Circuit Mender is an interesting upgrade to
Filigree Familiar that works well with flicker effects. Not sure if it makes the cut in Brago, but certainly worth consideration - I like the incidental lifegain. The 'etb: draw a card' pool is already extremely deep though.