Thanks for all the replies. As mentioned, I am a huge Osprey fan when it comes to packs for hiking and even fastpacking (just started to dabble in that sport!). I am using a small Mountainsmith pack that I bought years ago... it has held up well for what I paid but its starting to show its age (zippers are starting to bind).

I am really caught between going back to a messenger-type bag, or trying something that has been mentioned above. Decisions, decisions....