If you are that ambitious, maybe consider cut/weld the metal frame to reduce the bulk as long as strength isn't sacrificed. Check out my avatar, my unaltered alice frame is in a CDN grainer.
I'll admit, getting into a unit is a bit sluggish and awkward.
a good weld will make the metal stronger. when i used to work odd jobs in construction, some people would cut their wrenches in half and weld them back together for better durability. i personally hate external frame packs, except for the fact that you can tie and hang shit everywhere, but if you're old fashion, i think that making the frame smaller by cutting and welding is not a bad option as stated above. just make sure you can fucking weld!