Kovie wrote:
But right now I'm more interested in something that I can do serious
day
hikes with, and commute 5-15 miles each way with laptop, some books,
and a
change of clothes and shoes.

Put a rear rack on your bicycle and get some panniers. Four P-clips,
top of seatstays and bottom of seatstays will hold a rack very securely
if your bike does not have braze on mounts. Obviously don't try to go
loaded touring using a rear rack mounted with P-clips but for anything
less, it will work just fine.

Use the water bottle cages for fluid on commutes and anything up to 100
miles. You can stop and get more fluid on rides. And supplement the
water bottles with a regular Camelbak if you want more fluid. No need
to carry excess stuff on your back.