Looking for ideal EDC bag--popular clamshells or an Aer pack?

I have already narrowed my list to a couple solid choices to choose from. I am looking for some perspective, advice, and experience with regards to EDC since I will be moving to the city soon and this will be my first real backpack. Budget is $500 and value does not matter--I am looking for something close to if not BIFL, though I suspect all the packs listed below are quality in this regard.

• GORUCK 21L/26L
• Evergoods CPL 24
• Recycled Firefighter Battalion 24 Hr
• Brown Buffalo Conceal
• Aer Day Pack or Aer Flight Pack 2
• To much lesser extents (just for fun): Synapse 25 (super practical but not liking the aesthetics) and Mystery Ranch Kletterwerks Summit (somewhat similar to my clamshell options and seems to have some interesting designs)

My situation and requirements: I'm a software engineer. I have a slim build and am 5'11 at 150 lbs. I'll be carrying laptop, ereader, portable HDD, power bank, 21oz water bottle, a few small cables and a notebook at bare minimum on a typical basis--these are my essentials. I want to allow extra room for flexibility in scenarios such as bringing a small-decent sized lunch, umbrella, a jacket, or a weekend trip (where I will only be carrying the laptop and maybe its adapter and a water bottle. Therefore, the pack should not be a tight fit with just my essentials--there needs to be some additional space. Backpack needs to be urban and somewhat professional environment-friendly. That means slim, low-profile, and ideally not too heavy.

Before going through my considerations, I have a question regarding actual usage and workflow regarding clamshells and using tech pouches/grids to keep small/loose items in place:

I'm not sure if clamshell is still useful for carrying tech stuff. The reason I'm favoring clamshell-style is that they are typically more space-efficient (e.g. they can keep a slim profile for an EDC without sacrificing space). However, they usually have minimal organizational compartments. For GR1, CPL24, and BBC, I feel like at least a pouch is necessary to carry loose items like flash drives, short cables, lib balm, floss, and a spork. Maybe even a small case for a portable HDD (for protection) and laptop charger (to keep the compartment clean and free from dangling mess). The approach is to reach your bag, select the pouch you need, and retrieve your item that way, vs. traditional backpacks like the Aer backpacks which have compartments for you to put stuff in that you can retrieve directly. However, the Aer backpacks seem to have significantly less space than even the Brown Buffalo Conceal despite specifications (the Aer Flight Pack 2 advertises 21L and the BBC 19L--I'm almost certain the BBC actually holds a decent amount more than the AFP2 and I'm curious if any AFP2 owners can comment on the space). In general, traditional-style backpacks have better internal organization at the expense of internal space that clameshells offer.

The question is: for a tech guy like myself, will a clamshell still make sense? Curious how those who carry tech stuff feel in this regard.

As a tech guy, the instinct is to look at the Aer Day Pack (the Tech version is larger but provides a negligible amount of internal space) because of the internal organization. However, I'm pretty sure the Aer Day Pack will be a very tight fit for a weekend trip with only clothes and a laptop, though I'm curious how the Aer Flight Pack 2 fares in terms usable space. It advertises 21L but certainly doesn't feel like it makes efficient use of it. The Day Pack won't do well with packing cubes and I suspect the AFP2 won't as well. One thing to note though--all my other non-Aer options have a large secondary vertical pocket without any internal organization or structure. This means it won't do well carrying loose items because they get jumbled up and accumulate in a pile at the bottom of the bag and you are forced to either store very little in that compartment or use pouches. As quick access compartments, I don't really see these being functional ones.

Next is the CPL 24 and the Batallion 24Hr. The former is far much more popular and praised and I have a hard time finding real reviews for the latter, which is very similar. What I prefer about latter is that unlike the CPL 24, the fabric isn't a dirt/dust/hair magnet. It also seems slimmer and is lighter than the CPL 24. 22L is the perfect size for an EDC in my opinion and the CPL 24 seems to be dancing on the boundary of being a bit too large for an EDC. For the record, I am a lefty so that disadvantage of the CPL 24 does not apply to me. I'm curious if the fabric can be made less of a dirt magnet. Apparently it's from the coating--maybe it can be washed off This is actually somewhat of a deal breaker for me. Also, would like to know other differences (however subtle) that may make one a better choice than the other. I am sceptical of the B24Hr though in that I never see it recommended over the CPL 24. It also doesn't seem as durable and as "proven" like the CPL 24 and the GR1 is. In fact, people mentioned there is not even a warranty on the pack and in fact I cannot find that there is one, which is alarming. On an unrelated note, I'm curious if there are any news of an iteration of the CPL 24 in the works--it certaintly seems to be the most well-designed of all my options.

The GR1 must be considered because it is simple, durable, and seems to be the de facto bag for many bag users--that alone is compelling. I like that it's a no-frills kind of pack, even more so than the Brown Buffalo Conceal. It also appears to have the best ratio of size and space (is the 26L comparable to a CPL 24 in terms of size/slimness? Otherwise, I should only consider the 21L). However, I'm not so sure it's a great EDC bag (e.g. will a GR1 dissuade you from bringing it for quick errands?). It is also overkill in terms of durability, which comes as an expense of the form of weight (3.2 lbs makes it the heaviest option) and material in that it is rougher and maybe even to the point of abrasive. If I have to nitpick something else, it's that I'm not crazy with the tactical look. I don't plan to ever go rucking or use the MOLLE webbing, which would ruin the minimalistic look.

Finally, the Brown Buffalo Conceal pack needs to be mentioned. It is the most versatile EDC in terms of looks and size. I can fit everything I need there, but could I get away with going on a weekend trip with it? I only wish that this pack is slightly bigger and its secondary compartment has some form of organization (even a simple partition would do) to prevent a pile of items from sitting at the bottom of the bag. That, or an Aer-like true quick access pocket.

Any advice, suggestions, or comments is much appreciated--whether regarding a bag or an approach to using a bag.