at one stage i also wanted a lot of themes but now that i want to use dark mode i have to use the classic Poco Theme that comes standard with the phone but i can change the icons with an icon pack and also because of MIUI i can change the wallpaper and lockscreen

so realistically themes are not necessary for me anymore - you can make your phone be different just by using your own imagination and other available means - its easy and fun and you can keep changing it whenever you like so your phone never becomes static and boring

I agree I'm not into theme's as such but always on the lookout for icons so use bits and pieces from all over the place