The results in this Google Books Ngrams chart seem to imply that the terms, the scent and the smell are the most used.
In order to ascertain how neutral these terms were I selected the following criteria.
- smell of *
- scent of *
- smell of the *
- scent of the *
- smells good
- smells bad
The asterisk represents any word that follows the last term which Google Books has a record of.
Link to Ngrams Chart
Judging from the results, it appears that the verb smell is more often associated with the adjective good than with bad, at least in its written form. However, if one notes the different terms used with smell of; smoke, death, burning, and blood along with fresh, the sea, the earth, etc. it is clear that both pleasant and unpleasant odours are collocated with smell. Whereas the noun scent tends towards positive collocations such as: roses, pine, fresh, the sea, jasmine, the flowers.
Consequently, the OP's choice of Scents & Smells for her proposal appears to be a very sensible and objective decision.