It's basic 'give something at a cost' logic - you're getting more space at the cost of being slowed down a bit. Instead of not being able to take the items at all you can make one trip back to base or a nearby vehicle with storage. Also it's illogical to assume one 7D2D unit of feathers is equivalent in weight, mass, or volume to one unit of rocks - or one minibike, jeep, or gyrocopter for that matter, all of which will only take up one inventory slot - that's the inventory system, it's fine. Giving every item it's own volume, mass, and encumbrance value would be a logistical nightmare and a gamplay PITA. Putting a jeep in your pocket in that case would totally ruin those pants! I'm not even gonna think about the copter - that's the stuff of nightmares. :miserable:
I am a total packrat. The first thing I do in EVERY Bethesda game is open the command console and type "player.modav carryweight 9000" I play them as RPGs, not survival inventory management mini-games. The vast majority of loot in those games is just vendor trash.
I have no doubt even with the slight increase I'll eventually be modding in bigger backpack capacity if I feel I want it - still I get what TFP has done and see it as a genuine improvement. Albeit said before I fill my pockets and get my slow behind eaten by zombies...