Looking at your Heroic Butcher kill, I can tell you need to completely change your opener, and be better at utilising your cooldowns.
For the opener -
always begin the fight with max Chi by casting Expel Harm continuously pre-pull. Then, don't use the first FoF until you've built up some stacks of TEB, and use
both your CBs in the first 10 seconds. This is my event-log for Mythic Butcher a couple of days ago; I'm not saying that's how a perfect opener looks, but I dare say it's a very good approximation of one:
https://www.warcraftlogs.com/reports...=9&view=events
Here is a link to your own event-log; compare the first ~25 seconds of mine to yours:
https://www.warcraftlogs.com/reports...=1&view=events
In terms of utilising your CDs better; you cast your first Serenity 21 seconds into the fight, which is too late, then RSK - BOK and only then do you pop TEB. Then, 8 seconds into Serenity you start casting FoF, wasting 2 seconds of the buff.
At 1m 43s into the fight you cast TEB, then mess around with both a Jab, EH and CW before you finally start casting FoF - then, you pop Serenity when there's only 3 seconds left of TEB, and your TP buff wears off mid-Serenity as well. It also appears as though Butcher did Bounding Cleave while you had Serenity up; make sure to watch DBM timers, or you waste several seconds of the duration.
Always,
always, line TEB up with Serenity, and make sure you get the full duration of Serenity + FoF off during the 15 seconds the damage increase is active by casting one immediately after the other wears off
without them overlapping.
During the last Serenity cast at 3m 26s you refresh TP with 10 seconds left on the duration, and TEB expires as well. You re-cast it quickly, which is fine if you had 10 stacks, but definitely preferable to get the full duration of Serenity during the same application of TEB.