I completely agree with this. I’ve made lots of mnemonics on my own based around 2 radicals when possible.
As for how I managed to notice the bigger radical-combos, I used the Keisei-script:
This makes certain you recognize the radical-combos in kanji when present and their relation to on’yomi readings shared with other kanji.
So, it’s certainly possible to rewamp some WK mnemonics to acknowledge the larger radical-combos in kanji (given a new single WK radical name*) as they also help you realize the likely on’yomi readings of that kanji.
It makes pedagogical sense to me.
*of course, the Keisei-script already names these radical combos. So, it’s not like they are nameless.
