I know what you are talking about.  2WPS not only involves feeling comfortable in both directions… but feeling comfortable and precise doing the slant change itself.   And on top of that… I remember mixing in economy picking into all of this.  It was a lot of stuff to maintain.
But I’m happy I did this… since I was at a plateau… and all these new mechanics gave me a lot more things to explore.  And ironically… it led me to my current form which is ‘slantless’…  But I still do a bit of pseudo-2wps when I do high speed 3 note per string runs where I arc more on one side than the other when I am string changing.
The only mechanic I can say that I regret learning was economy picking.  I know there are others that are excellent economy pickers… but I could never get it to sound the way I wanted it to.