Be careful about your 5 days of food. Repack the food into zip-lock bags. This reduces a LOT of bulk. I really do not find much difference in gear I take on a 2 day vs 5 day trip. I think your pack is sufficient, but you may have pack it more efficiently. Fill up all those little empty spaces. Be careful with little stuff - take the small "travel size" for sunscreen, toothpaste, etc. Maybe substitute a kerchief for a bulkier camp towel. Sleeping pad for some, is one of their most bulky items. I switched to an inflatable sleeping pad and then just take one 2x2 ft square blue foam for a "sit pad" - this is less bulky than one large foam pad. These are just examples. I am sure you can find ways to reduce bulk of your specific gear.

I am not familiar with your pack. I personally prefer a pack with one large compartment and have actually cut out internal dividers. If the capacity of the pack is divided into too many small compartments, you loose effective capacity. If your pack is highly compartmentalized, rethink what goes where to more effectivly utilize space.

On the other hand, if you are looking for a fine excuse to buy an new pack or upgrade, go for it! There are lighter and better packs out there. But do not necessisarly buy a monster pack.