I previously posted this: Looking_for_my_first_carry_on_sized_bag

Since then I've looked more into bags and tried some and have narrowed down my criteria (and pick up some new ones too), but still haven't been able to find a suitable one. I believe what I'm looking for prob doesn't exist, so there is something wrong with my expectation, and would like honest feedback from you baggers.

My aim is to travel few weeks at a time, and care the most about comfort (don't wanna deal with back and shoulder pain and looking for a place to sit every 20 minutes again a week into a trip). I'll spend most of the time in cities, with some day hikes. I spent hours looking at and trying bags at Patagonia, North Face, MEC and a few other stores with backpacks, but couldn't find something that I liked.

This is what I gathered:

• Many travel bags are made at or near 45L. I personally find those too big and know if I buy one, I will fit it all up and end up with heavier gear.
• Shoulder pads on a lot of the 30Ls aren't any different than the 20Ls, and they rarely have hip belts. I found this very confusing, why make a bag that if fully loaded would be uncomfortable on the back and shoulders? Are you not supposed to walk around for long with those?
• Top loader bags mostly lack a decent organization pocket outside of the big bucket. They also usually don't have a side zipper to access the bucket from the side. I found undoing top straps unrolling the top and/or uncinching diving in the bucket to grab something quick too clunky. But they seem really nice for long hike or camping. They tend to have nice back support.
• Suitcase opening bags make for a really good experience if I were to stay at one spot for days at a time. But jumping from one hostel to another, or wanting to grab something quick when there are no external pockets is also clunky with these. This is less of an issue if there are other decently sized pockets on the exterior. They tend to have less back support.
• It's important to try a pack in person with weight. All these bags feel different, and are organized differently. So if you're gonna carry them fully loaded for any significant amount of time, I suggest trying on in person as opposed to buying online.

I'm looking for a bag that:

• Isn't too small nor too big. I'm looking for a backpack in the 30-35L range to bring in on a plane. Anything larger is too big and bulky. MEC had great selection for 45L for outdoor activities, but those are way too big. All my clothing that I will have in the bag will be 15-20L, so I find anything less than 30L a little too small.
• Is comfortable enough to walk around for a couple of hours. So
  • Has decent shoulder straps
  • Gotta either have load straps, or hip belts or both. Or at least hooks for optional hip belts.
  • Hip belts that are the same material as a seat belt don't count, those felt more uncomfortable than supportive.
• If it's a top loader or suitcase style bags, it should not have the "clunky" design I mentioned above.

Nice to haves:

• Hip belts are either not huge, or can be removed/rotated to take less space when not needed.
• Smaller pockets for quick access, ie not just one big bucket
• Laptop storage (almost a necessity for longer trips)
• Straps and rings on the exterior to hook/carry items on a pinch or a jacket, etc
• Some structure to the back piece

At the end of the day I want the bag to be comfortable. Do you have any suggestions? Am I looking for something too specific?