My wife and I own seven backpacks.
Everest travel backpack - My SUL and dayhike pack, just got this a few weeks ago and am very happy with it after going on a few dayhikes. On my scale it is only 350g.
Generic cloth backpack - Wife's dayhike pack and my old SUL pack. Have no idea the brand, just a simple pack with straps, a main pocket, and one small pocket.
Golite Jam - Go to 3 season pack.
MYOG pack - If I am not going through thick woods and just sticking to trails I will swap this in for my Jam, as it is a bit fragile, but only 450g with about the same volume (maybe slightly less) than the Jam.
Osprey Kestrel 48 - For winter or if I am going with a group and we are doing fancy meals, i.e. fresh veggies/fruit, bottles of wine/whiskey, etc.
Two generic backpacks - Again, don't know the brand, both were bought on sale for cheap, and both are very tough. I am guessing they are both about 30l and around 1kg each (never weighed them), lots of padding and thick hip and sternum straps and very comfortable. These are our urban and roadtrip packs mostly, and I also use mine all the time for school. My wife uses hers for backpacking (I used to use mine before the Jam replaced it), as I am the one that hauls our shelter, cook kit, FAK, and lots of other gear we share, so she does not need a high volume pack and does not give a hoot about going UL (mostly because I am the one hauling the lion's share of gear, I think).
I am proud to say that while we may own "a lot" of packs, they all have their place and all get used.
I would think about buying a GG G4 or a ULA CDT if I had the cash to throw around (always nice to have more options), but right now I am very happy with my set up.