The icons and trading screen interface look alright. You need to polish up on your detail and shading. The hats are plagued with problems, but I doubt you want my to run through them all and make them seem dreadful when they are not. Take a look at a few guides on line art, they will really help you.
Nevertheless the Gate(s) look great, not sure how different it is from the original picture that you 'modified'. Good luck with more futuristic style graphics. Keep us posted with any progress <3