First of all, thank you for your video player.
I'm gonna leave my requests that I miss and hopefully will be useful to other people.
It will mostly be things that I immediately miss coming from smplayer.

global volume: The fact that kokovp always start at 50% is a nuisance. Make it remember the volume or make it global.

subtitle track: This I solely miss especially when watching anime with several subtitles tracks.

For what ever reason, kokovp does not remember window size when closed. I can force it to remember using KDE windows rules but, it should do it by itself.
For me it always opens like this and I assume "kokovp" is supposed to be middle aligned.

Seek to position while dragging is not working for me ? Both do the same thing.

Video options are .. :

vs

It should be possible to click the seek bar anywhere and jump video to where you clicked.
Seeking with the keyboard is very slow. I have 2 seconds set for shot jump. If I keep my left or right key pressed in, the seek performance is for lack of a better wording, bad. It does not react, it stumbles and lags instead of keep seeking instantly.
I miss some kind of visible chapter marker, somewhere.

How do we customize "mpv" options ? Some I use e.g:
video-sync=display-resample
interpolation-threshold=3
interpolation

Thank you for your time on this project. Keep at it. It's already awesome :)