Looking good, mate.
Keep it up!

As for looking 'cartoony', I must disagree.
People have very different styles when it comes to making scenery in the same way peoples painting styles vary.
Some people are very different to others and do not match well, but if you are making all your own scenery for a project, the overall effect will look great.
Having a distinctive style is like a signature.
Your style reminds me a little of Aggro84's buildings, which I happen to think are wonderful creations.
Keep on building.
Now!!!!