Research is the place to start, and you've picked the right place. There are three places to begin on The Barrow-downs before even needing to solicit opinions:
1) THE BOOKS forum. There you'll find some of the best discussions on the Internet of some great Middle-earth topics, including the ones you've mentioned (or topic that include yours).
2)
The Middle-earth FAQ: compiled from this very forum
3) Our
ARTICLES section on the main site.
Once you've been through this extensive group of discussions, you'll have a wealth of ideas for you thesis.
<font size=1 color=339966>[ 9:35 PM January 08, 2004: Message edited by: The Barrow-Wight ]