OMG there are SOOOOOO many other places besides the obvious such as Market Street, unless you want the same old uncreative pictures like everyone else has in The Woodlands w/a bunch of messy dressed strangers in the background, unless you have the patience to wait until they move out of the shot. I'm assuming you are looking for less popular and less populated areas?
-All along the waterway are hidden treasures of photo ops tucked away here and there, from Grogans Mill to the highway - water, bridges - maybe you'll even get a shot w/a duck or two swimming by in the background.
-All around the edge of Town Center there are hidden paths on both sides of different levels of quaint landscaping.
-you can get some nice water/city shots from one of the watertaxis while its cruising
-The multi colored apartments (don't know the name) along the waterway has little courtyards off Riva Row - you might even catch the fountains flowing.
-If you are looking for more wooded shots, try any of the parks - they all have patches of landscaping and trees and wooded areas
-Terramont Park off Terramont Dr and Branch Crossing on the East side has a nice hill. Its used for frisbee golf but overlooks the soccer field, skatepark, basketball and tennis courts and playgrounds
-I actually had some Mother's Day pics taken at the entrance of Landry's and if you angle the people right, you can't even tell its at a restaurant. Brio's is the same if you stand on the patio overlooking the water and someone takes a streetside pic across the water
-See if any of the country clubs or the new high school will let you take photos on their grounds.
Good luck to you. HTH. (I really hope you don't end up at Market Street like everyone else!)