My dissertation was survey based. I used three different questionnaires that have been validated and are widely used, in addition to creating another measure.
I wouldn't necessarily say using surveys are 'lazy' (I can see where you're coming from when you use other methods, and to some extent I can agree), but if you only use one survey to assess whatever it is you want to do, then I would assume it is a pretty poor project.
Ultimately, it all depends on what you want to get out of your dissertation and what kind of area you wish to research. I wouldn't advise choosing a topic where you can get away with just using one survey. You have to remember that you're generally going to be writing approximately 10,000 words, and you need to find a lot of research to support/oppose what you want to find, and what you do find.
With regards to personal details: Some studies won't require any personal data, some will. Generally, most studies will only ask you for your age and gender/sex.