Some very useful tips to improve your aims/thesis statement:

from http://jerz.setonhill.edu/writing/academic/thesis.htm

Useful Formulae for Thesis Statements

If you're not sure whether you have a good thesis statement, see whether you can fit your ideas into one of these basic patterns.

• [Something] [does something] because [reason(s)].
  
• Because [reason(s)], [something] [does something].
  
• Although [opposing evidence], [reasons] show [Something] [does something].

For longer papers, thesis statements can be very complex.

While [a specific, named person] says [a direct quote or paraphrase from the source], [a different, named person] says [something else]. While the two authors disagree over [a minor point], they both share a deep concern over [the topic of your paper]. [Person one's] refusal to accept [a particular point made by person two] suggests that [person one] is [your thesis -- stating the real reason why person one won't agree with person two].