I really like this one! proportions are great and the layout is really cool IMO.
can I use it to make a more cartoonish & detailed drawing in photoshop? (not for any commercial purpose of course, just for fun)
Feel free. It's an unfinished adaptation of a model of the old town of Stari Most, part of present day Mostar in Bosnia Herzegovina, available on Sketchup's model site. Suleiman the Magnificent would be flattered with your appreciation of his commission I'm sure.
I'd be interested in having you do a commission for a castle in my DND setting. Are you interested in Commission work?