The artwork is cool.
I assume you don't intend to shoot it much though? You made some real nice places for that slide to crack.
I actually do intend on shooting it. It's going to become my primary carry gun. I wasn't worried about anything until you said it. LOL
Just shoot it a bunch and keep an eye on it then. You'll want to regularly inspect the sides of the slide where it's thinnest from the arms of the cross; that's where it'd most likely crack if it's going to. Better to catch it during practice than when you really need it.
Actually, on second look, better keep an eye on all four points of the cross; the area at the front of the ejection port takes a beating and could eventually crack there too; just watch it closely.
To be clear, I'm not trying to be a negative nancy; I've spent the last 20 years in durability testing and a big part of that is predicting and finding cracks in steel parts, much like your slide. Just commenting based on my experience there.
It does look good though, no doubt about that. Did you have it done with a laser engraver, or CNC milling? I like the aged metal appearance too, is that a surface patina or a coating like cerakote?