There are many wonderful machines...
Centaur (coolest look... and also speech ever), Fathom are top of the top - best backglass ever... Viper (Stern 1981). Medusa is also super nice, but I don't like the gameplay at all. Quite a lot of the Stern EEs are really nice.
The AFM backglass is for me personally one of the best... I also like the artwork of the cabinet and the playfield... but in this case, I am not objective, because I like the gameplay that much.
The Big Bang Bar has a unique and absolutely great look. It is a pity that you have to pay ca. 15k here for this beauty. This is too much for me, even though the artwork is in my personal top 3.
Also in the top 3 - the X-Men. Out of the box Magneto is first choice. But I bought a Wolverine - with glossy black powder coated siderails, lockbar, etc. - this will turn the premium choice.
The comic-style, aggressive look is closer to pop-art than to a gaming machine. Great job!