For a lot of hiking, ~25# maximum load follows easily. Most of us do not do through hikes. Most of us do not do winter hikes. So larger volumes are not needed. It sounds like you have your gear fairly well dialed in to the light weight category.
The weight should not exceed 1#8 in any event. Even that is a bit heavy for a UL pack, but anything up to two pounds will work. Anything heavier is just hiking dead weight. There are many packs <2# that can do the job. The Gossamer Gear Mariposa was BPL's choice this year. The stay works well if you already carry an inflatable pad. Otherwise it is possible to add several layers of sit-lite padding, cutting/fitting them together into a 5 layer pad that *just* fits into the pad keeper. You can then drop the internal stay, using the multiple layer foam as a frame. This also saves about 400ci in backpack space. The Gorilla is somewhat smaller, but works the same. Note that none of the GG packs include the extension collar. They are larger than what the specs say.
They generally carry fairly easily, with stay or with foam frame. The 25# weight limitation is really not relavant. All the packs in that size range will work. I usually use the Murmur at 35L and 25#. It doesn't have a stay. It is UL fabric, though, and you mentioned some bushwhacking. So, I won't recommend it. Even though it fits the other criteria. (I know it says 20 pounds, but it carries 25 easily through the ADK's.)
1) You might consider adding side pouches for carrying water. These can catch if you are bushwhacking, so, should be fabric, not mesh.
2) You should consider breaking your gear up into two categories: Can get wet & Never gets wet. (This means sleeping dry despite days of rain.)
3) A good hipbelt, not one that is just overly padded. Most of your weight will sit here. It should wrap around your lumbar and sides.
4) Good shoulder harness, not fancy with bells and whistles. Just simple and effective. It is nice to have one loop on one of the straps, though.
5) A good internal "water" sleeve. Nope, never use a water bottle there, I put flat items or sharp items there. Stakes, spoon, pot lid, aluminum foil, car keys, and so on.
6) Load transfer at 25 pounds should be good to excellent. After a day or two, you can accommodate to most packs with 20# or less. But you need at least a good transfer for 20-30 pounds.