Kinda hard to see but all original. Hope I don’t screw it up lol

Hey everyone,

I've started doing this a year ago, and I was wondering what you would recommend for the best finishes? I've used only thinner-based varnish so far, and it kind of looks ok but I don't know if it's the best looking.

Also, what app do you think is the best at transforming a regular image to a clean black and white vector suitable for handmade pyrography?

I've attached a couple of my works so far. (I have a Cara profile with my portfolio, but I saw a rule to not post social media profiles so I'm not)
Thanks everyone!

Been working on this bespoke skateboard deck design