the buildings look good from the thumbnails... i have trouble with buildings... mostly i just draw faces... so i am challenged by doing much more... even though i paint whole scenes and such, as you can see on my website...

but in most of my paintings i keep it pretty simple...

it looks like you have a good sense of shape and composition... so it is just a process of refining your details i guess...

and for that? practice is likely the best solution...

phil