I do not have Adobe Premiere but what I can suggest is to stay away from the Cinepack codec. One of the worst available. Try something mp4 or similar.
Although these are for video sharing sites, they are valuable info on quality compression:
http://vimeo.com/help/compression
http://www.google.com/support/youtube/bin/answer.py?hl=en-GB&answer=55744
What I generally do when exporting image sequence is to export it at double size then resample the images in an application that supports batch processing with nice antialiasing. This will also make your edges a bit thinner and first of all, much crisper than the normal SU output. Then use a compression type that does not destroy the quality too much (Cinepack does unfortunately).