The artist I’m working from is Mark Weaver. These are mostly done in photoshop, with some illustrator for the little type I added and also the outlined car. I tried to get the vintage 60s feel of much of Marks work by using a grainy filter as well as tinting the colors. Mark combines mountainous landscape with architecture, so that was a big aspect I’ve been including. I also have one trial including animals/a skull with a human body, because he has many pieces combining human with other mammals heads. T1 – 6 of diamonds. T2 – King of spades. T3 – King of spades. T4 – King of Diamonds
T1 
T2 – I like this one a lot, and felt adding architecture to the front could be too busy. Maybe a simple building could be a good addition though? 
T3 
T4
These are awesome! Clearly you’re having some with Weaver’s retro-futuristic collage style. I’m curious if you used the match color feature in Photoshop since the landscape colors are dead on with his palette.
A few minor suggestions:
In the Elvis piece, scale the figure so that the raised hand isn’t so close to the top. And maybe try scaling the car down a hair so the cab feels more centered. And maybe outline the spade instead of a solid fill.
The skull piece is great too. The 6/Diamond are just a little crammed in the lower right.
In the Kong piece maybe try different placement/font or value/texture for the 1933.
I didn’t use the match color feature, although that would’ve been helpful! I just edited through color balance, lowered saturation, and used a sepia filter. Thank you for the suggestions!