Well, my take on things is that if you stay in survival you'll feel more achieved after completing big projects. However, creating in survival will take longer than creative. Creative is the exact opposite; you'll build quicker but won't feel as achieved. Of course, if the project is huge and you think will take months or weeks, definitely go to creative. Once more, on the other hand, if you have the materials for it and the time, just go survival.
tl:dr My say is that you stay is survival mode.
