Nice! I think it sounds really good. You asked for tips…
There was a period where I was obsessed with Michael Hedges and Phil Keaggy and did lots of slap harmonics on the acoustic, that was like 10 or 15 years ago though. BUT, I’ve also done a lot of jazz and classical artificial harmonics more recently and the principal is the same. The best clarity comes when the harmonic occurs right over the metal part of the fret. See this crude image:
So if you’re fretting the third fret and you’re doing the harmonic at the 15th, you need to do the harmonic right over the fret itself, which is different than how we fret notes, and we’re slightly behind the fret with our fretting hand. All harmonic (natural, artificial, touch/tap) follow that same principal.
I can’t tell if you’re doing this or not and like I said it sounds really good. Just thought I’d mention it in case places where you feel the clarity is lacking, maybe it’s just a tiny bit off the fret or something. Millimeters matter the higher the fret numbers get. I know in the acoustic stuff I was doing, if I were slapping a ‘chord’ that spanned several strings and it was anything more complex than a barre…it’s pretty much impossible to get total clarity out of each note haha. I’d just kinda angle the slapping finger sideways a little and get in the general area (12 frets above) my fretted chord and hope for the best lol
Anyway again, great playing! If you’re up for a little inspiration on taking this stuff even farther than EVH did, here’s some cool Keaggy for ya! (sorry about the shit quality…can’t find a better vid)