Hot take: I much prefer how Sunrise are using the forgotten demons in Yashahime than they were used in the original manga.
In the manga, most of these cool demons were fodder for Moryoumaru and/or Dragon Scaled Tessiaga. In general, I really disliked Inuyasha's dragon scales power up because it was hogging the screentime. Kikyou even warned Inuyasha that a sword could not defeat Naraku. But he ignored her advice and spent the next 50 chapters chasing after a powerup! Even Naraku thought it was a joke and fed Inuyasha those demons!! It ended up being such a dumb meandering plot line. (And don't get me started on how Moryoumaru just guzzled demons to form the ugliest body ever. Such a waste of cool demon design).
At least in Yashahime these different incarnations are being incorporated into the plot to help the girls discover themselves and further the plot. Meioju and his son was a much better use of screen time because the girls get to be sympathetic to their cause and help the dad rest in peace! So was the Cat Monk, which made Towa develop her powers in a way to help people. And now Kinka and Ginka serve to actually draw parallels between Towa and Setsuna. All of these make much better backdrops for Yashahime! We get to appreciate Takahashi's creative designs without being bogged down by bloated sword power ups!