Thanks for the info IL. I have been doing partial boils, about 2.5-3 gallons. On the first 2 which are the only 2 I've tasted I did all extract upfront, per instructions. I'm guessing that's a big cause of the flavor(toasty caramel, bready) but as I move along I hopefully can pinpoint for sure. The first 2 I also didn't treat the water. On the 3rd batch, I treated the water with campden AND did late extract that but that one is still fermenting and I haven't tasted it. Maybe once I taste it I can compare but the first 2 were IPAs, the 3rd an amber so that could make comparing a bit difficult.
Yeast on all my batches has been US-05. I'm wondering about oxidation as well. I've been very careful with the fermenter and I thought my transfer to bottling bucket was pretty clean, but who knows.
You're on the right track!
Some brewing salt additions benefit the taste perception of beer, maltiness, bitterness, hoppiness, softness, among others. Without knowing your water composition, it would be difficult to advise what to add at this moment. Some taste tests using small amounts of dissolved Gypsum, Calcium Chloride, or even salt, added to a glass can reveal some of that. John Palmer even advises (extract) brewers to brew with RO water. You can probably get it from a machine at your supermarket or Walmart at $.30-60 a gallon, or use distilled water.
In any case, a Campden treatment is essential for any (municipal) chlorinated water. If your Amber tastes especially very clean then you may have solved that problem.
US-05 is fine. Did you rehydrate the yeast (according to Safale's instructions) and aerate the wort right before pitching? Obviously I'm still a strong proponent of (proper) yeast rehydration before pitching.
Having CO2 available makes it easier to purge air from fermentors, bottles, etc. But without it there are many ways to avoid, limit, or at least reduce air ingress.
If you use buckets, a tight fitting lid surely helps. If your airlock bubbles, the lid is usually tight enough.
When you know you'll be dry hopping, adding fruit, juice, syrups, wood, spices, etc, drill a 1/2" or 1" hole in the lid, pretty much anywhere where you can stick a rubber stopper in it and won't be in the way. I recommend opposite from the airlock, or in the center, if that works for you. When dry hopping (or adding anything else) you have easy access without taking the lid off. Preserving the headspace rich in CO2 is very important. The larger the hole the easier access, but also more CO2 will be lost when opened.
Careful handling while racking, priming and bottling also reduces air ingress. Cap on foam if you can.
Or look into kegging and using a CO2 tank to eliminate all or most air exposure.
