You'd have to test the even lower stack. It's one of those things "lower is faster till it's not". As in you wind up gaining 1w but lose 10w on power production from the hip angle.
Looks good to me. If it were me and you hate that helmet I'd try a Poc Cerebel. It's a bob tail that's roundish, easy to find, tests pretty well on most folks.
My hangup with that Facebook group is that I've been finding some advice I got earlier starting out TT was good for starting out. And that group is good for that. I used Slowtwitch to get help. The tweaks that started to get me somewhere were using Golden Cheetah and virtual aero.
How narrow are your pads? I think you're just a small dude given where your arms align with the rest of you from that view.
As I got faster from the 23-25mph area to 26.5 to 28.5mph range the suit choice changed and I feel I got some there. I haven't tested that with the Notio yet, but my Aerocoach/Nopinz suit just always seems to freaking fly when I use it.