There are effects the Kemper can't produce, I've got a board with a sitar emulator, sequenced bit-crusher / filter, synth and others from the H9, a gamechanger plus pedal, and a CBA Habit which is utterly ridiculous, the profiler can't really do any of those things. It does completely remove the need for 'normal' pedals though, which is great as it means my pedal budget can go entirely on fun weird things! So I use the profiler's compression, drive, reverb and delay along with any EQ that's needed, and if I want something more 'magic' I can add in this board and go to town on it.
I look at it like this. How many times in the night are you going to use a sitar emulator or a sequenced bit crusher in a night? For like a song or a 15 second part? For what it takes dragging it around the audience would likely never know if it wasn't there and you had something close. I recall someone having a sitar emulation effect that was pretty good that I recall messing with, (likely in an artist/legend pack as I rarely find much useful in RE). There aren't many useful effects the kemper can't do just the weird stuff that wouldn't get used much anyway. That's just me, if someone wants to go through all the bother dragging a POG around for a 10 second part more power to them.