This felt like the best composition for the station (my subject), but not necessarily the background.
I guess the above is probably the main issue here. What do you want to convey? What did you find interesting in that scene? What should strike your viewer? Which kind of feeling(s) moved you to press the shutter button? Do you feel that same feeling(s) again when you see your picture? If you answer those questions, a couple of possible compositional choices will spring out.
Do you want the contrast between blues? then why there is so much of non-blue stuff in the final picture? Do you want the decay? then why did you remove the cracked line in the asphalt? Do you want the contrast between orange and blue? then why the orange stuff is so small/irrelevant in your shot?
I have collected below some quotes of what you said above about the scene and your intentions, with some brief comments/questions. Perhaps reading through them will help you focusing your interest, which is what eventually makes a shot, or destroys it. My impression (but I might be wrong) is that you are trying to include too many things in your picture, probably far too many for it to be able to say anything at all. A picture cannot be an encyclopedia of feelings (well, a few can be, but that is a hard feat for most of us). It is generally easier to focus on a simpler message, and stick to it.
The shot says nothing to me, but I am generally not especially interested in colour shots of petrol stations, mind you!
FWIW, none of the alternative renditions proposed here says much to me, not even the reduction to monochrome. They all feel "cold" and flat, some of them confusing and lacking focus (on a feeling!).
And remember: you cannot make all your critics happy
If you asked 100 people, they would have made 100 totally different shots, but all of them without any relation to
your shot. You should focus on what is the impression and feelings
you want to convey.
And do not fuss around too much with straightening vertical lines: we do not perceive them as straight anyway, most of the time. Rules are made to be broken, if needed, and in creative ways, if that works to convey your feelings. In the same scene, I would have probably tried a very short focal length, I might have attempted to put the camera on the ground or very close to it, on the leading crack somewhere, accentuating the converging "verticals", making the whole structure towering up against the sky while making all the background stuff microscopic and irrelevant.... but that's me, not
you, and perhaps the angle and composition I have in mind does not exist at all....
Take all the above for what it is: the personal opinion of a total stranger. Most importantly, just keep shooting and keep it fun
OneEyedPainter (quotes below)
- I may have been able to position the orange sign behind the support post differently, but I opted to just split it symmetrically instead
If the sign is important to you, why is it in the background? I did not notice it at all initially....
The blue is what attracted me as well
Then why there is so much non-blue stuff around? Does it help to focus on the blue, or does it distract the viewer from it?
I wanted to capture the decay to contrast the blues
There is little sign of decay in the picture. The pumps themselves look like they might still be working just fine.What says "decay" to you there? Does it have a sufficiently central position? is it evident or subtle?
The harsh light creating different shades of blue that complement the sky was what made this rather boring and ugly thing interesting to me
The only shades of blue are in the roof, in the sky, and in the sign on the right. What is most relevant? See the comment by
@Vaughn . How about all the rest?
The harshness was an intentional choice, but the shadow's location is not very interesting to me.
The harsh light is what creates "dull" shadows. Light is what makes your picture (literally). Perhaps try different angles or different times?
I do like the leading line of grass in the pavement crack going towards the station though
But then, you removed it from the shot. If you liked it, is there a way you can include it in your shot?
. Like many things from the 2010s the design language of these everyday objects are boring as heck.)
, which is to say that some times, even if you have a subject you really like, best thing to do if you cannot get a satisfactory photograph out of it is to let it go 
...