Once I got over the -filter_complex is well, complex phobia, it isn't that bad. The command line makes it look daunting to be sure. But thinking of it as the name suggests of "filter chains" makes it less daunting. It is still cumbersome as every thing needs to be in the command.

Debugging commands gets hairy the more complex they get but you'll get muscle memory on how to search/replace to make line breaks to make it easier, similar to breaking up gnarly SQL. The worst part about debugging is the error messages can be misleading when it interprets the filter chain incorrectly because of some issue you've typoed in there somewhere. Even those start to become recognizable as "it thinks this, which means I probably messed up this other thing instead". To be fair, I work with ffmpeg daily using some commands that make your eyes bleed. So for someone using it every now and then, the practice from repetitive use just takes longer.

Also, saving things as shell scripts helps a lot. A simple script that does the same thing with a few adjustable params can be done with %1, %2 usage or even cleaner with getopts. You can then change small things within a tested complex command.