You Know that Kaiten still exists in PvP and it turns Single Target Attacks into AoE, which works for PvP not so much for PvE.
That Stance thing sounds like Sage to me tbh, you would just hammer down the same rotation but it's AoE now.. ehh
also why would you change Kaiten like that? Currently with the Auto Crit on Midare and Ogi Kaiten should turn the next attack into Direct Hit, rewarding Resource Management that way.
Fuga overlapping with Yukikaze WHAT!? Fuga is a Combo Starter Yukikaze is a Combo Ender, I already mentioned that the Idea of merging Shoha I and Shoha II may've come to the fact that the English Translation Team just did not care.
So that Stance Suggestion squanders more than it is contributing but with the Uselessness of Kenki the Devs may gut everything about the Samurai due to too many conflicting demanding voices.
that Ikishoten suggestion already exists but here again:

/macroicon Ikishoten
/ac Ikisshoten
/ac Ogi Namikiri

that macro does exactly what you're suggesting though we may see a Single Target Ogi in 7.0 anyway

well your suggestion not only saves 8 buttons but it also changes the Samurai and turns into a Sage with a Katana, I'm not sure if that Switch pays off and I doubt it.
+ Stances for DPS are unlikely to be added anyway so what's your points? if you only want Kaiten why do you suggest merging Shoha and Shoha II and Senei and Guren? by merging those skills you disregard decision making behind it and in turn disregard a Part what makes the Samurai a Samurai.