I personally like modular packs that can be run w/o the frame for day hunting and yet can still get a load out on the first trip.
I bounce between my Nimrod, Oregon Pack Works (Orion) and my Wilderness Packs Specialties "Compact Combo".
But my goto pack is a hybrid....the Nimrod Pinnacle Pack w/ WPS Compact frame & Nimrod Wilderness Gear Bag (firefighter model w/ the side pockets). w/ DIY pods added as nessesary.
Most of the time I'll run w/ just the Nimrod Base Belt Harness and a set of simple DIY meat straps that buckle on the back. This allows me to run w/ a 3lb harness w/ ~600ci pounch on the back, just large enough for basic day stuff and UL meat bags. When I kill I just pull out my meat straps loop them around a qtr or two and buckle them on the back.
Other times I might be running w/ the frame buckled on, in which case I can use the WPS "Handi-Pak" meat harness/load panel. I modified my WPS meat harness and sewed on a couple sets of PAL loops to accept a MOLLE sustainment pouch to give me the option of adding a little extra food & water for the day.
Of course I can also add the Nimrod Pinnacle Pack w/ or w/o the frame. Basically I use this pack body for my overnight/extended hunt gear. More food & shelter gear. Being a horse guy I have to admit this config gets used a lot. If we kill a long ways from base camp, we have just enough gear to build a fire, throw up a fly and stay relatively comfortable for the night. Heck night passes pretty quick when your roasting tenderloin on a stick and passing the brandy bottle back/forth. (wink)
If I'm going in multi-day on foot, I add the Nimrod Wilderness Gear Bag for my sleep system, jetboil & food. And I'll add pods as I see fit to accomodate clothes.
Once I get to my base camp, I'll unbuckle most of these components and leave them in camp and run once again w/ only the Base Belt Harness....and maybe the Pinnacle pack. My GPS, Radio and binos all hang off of the harness. I do have to point out, I don't use a tripod/spotting scope, so I don't have to accomodate packing those. All I need are my binos and the 20x glass on my rifle.
Anyway that's what works for me.
Hunt'nFish