the Design is all inn the Bag: Good Design For all.

Frame packs are the essential piece of equipment for backpackers to carry all their gear. There are different types of backpacks, internal frame and External frame. Internal frames are more common for long hikes and extended travel because they pack up tightly and is thinner on the sides. With the internal frame the suspension system is much better and makes carrying heavy weights easier by putting all the weight on the hips.  An external Frame is used for short hikes (2-3 days), they are made to hold minimal gear and spread weight of pack out just enough to make it carry able, (some weight is put on shoulders).  

To have a well Designed frame pack, first the pack must be the right size for your body, second, you should have the pack that best suits what you need it for, so for a short trip smaller pack, no need for a pack that is made for a thru-hike of the Application trial. But if you are planning on roaming around Europe all summer and are going from the alps to the sea then a large pack is what you need. 

Then each pack needs to be fitted to you, have someone hold the pack above your shoulder and then clip and tighten the waist belt then slowly lower the pack and tighten shoulder straps.

A good pack will make the load bearable but some blistering is unavoidable, but the load should be on your hips not your shoulders.

The right pack will do the job, each pack is designed to fit a need, and made to carry gear in different climates. The "good design for all" is all dependent on if you know what you need in a pack. 

Picture yellow backpack: http://www.google.com/products/catalog?hl=en&client=firefox-a&rls=org.mozilla:en-US:official&authuser=0&q=internal+frame+pack&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&biw=1366&bih=609&um=1&ie=UTF-8&tbm=shop&cid=12831094982018552951&sa=X&ei=R1uDT9_NMIqk8QTcuanWBw&ved=0COMBEPICMBM

Picture: blue bag : http://lh5.googleusercontent.com/public/hODk6tOKUsHJ1PZIgRo-vDCeVE4D8Gf9_88_2_Sq4uXbgtXy0QHAuyjeA2GaJOMjV4CUMG7o0QeAifgJQBZPPCDZBO_GgX4S_6FeJiyilW3kmudu9i0AbmdaQsYU_rVq-bfEmYA4fZKHbtFRVG9IJGynd9jKQNbE-oR2nOrIoho7iFIIOM0eufPR31qKJWzLYXLviFgdpRvFmv3dH70xjvDQy7q2hovxruRwKejtd0wEAyYgXL1A2EOlp5q7WKxLm3CZDtmGwI7_qizh3TXh0T_OsmIrxZf8k9HUblzgZO5esvOE