Regarding the sv changes at 01:24:002 - & 01:26:912 -
Taiko RC (Kantan) states under Guidelines:
"Slider velocity changes may be used cautiously. Changes should only happen for sections of different pacings and slider velocity should not be drastically variable."
"sections of different pacings"
This would mean the whole Kiai, which you've applied correctly using x1.20
Though, that finisher 01:24:002 (108) - is using x1.40, which makes it faster.
Kantan is meant to be played by literal beginners, and as such this sv usage might not be suitable for this difficulty.
I suggest to keep the finisher at x1.20
I also suggest to move the slow down at 01:26:689 - back a bit, so that it only affects the spinner which is on the section change.