What you're doing is comparing a relatively large damage difference to an incredibly small damage difference. If I wanted to say that it was ideal, I would, however I personally never mentioned anything about posting an "ideal" set, in fact when I posted a set I specifically mentioned that I was not including Khepri due to the small chance of getting them, thus posting a sub-optimal set that is still well into the range of top-tier equipment sets.
Also worth noting that Thaumas pants, Mantis eye, and some other gearswaps would be optimal on certain NMs where your hitrate is uncapped. There is no single ideal gear set.
However I can say with utmost confidence that 0 ideal gearsets will ever include a Khanda.

