Check out Tactical Tailor http://www.tacticaltailor.com/
or for the same quality at a reduced price, the one I have, the Gray Ghost 3 Day assault pack.
https://www.greyghostgear.com/

I also have the Maxped Condor II. It is a 23lit pack that I could pack for a weekend and not feel as if I was lacking in anything. This of course takes into account utilizing all the molle webbing and straps on the pack.

Now MOST folks would probably say the Condor II is small for a weekend trip, and yes they would be right, but it CAN be done if you carefully choose your gear and utilize both the inside AND outside of the pack. Personally for a weekend I would recommend the Three Day Assault pack as it does allow for more gear to be carried inside the pack.