It sounds like you're being very analytical about your process and following the great advice from the forum. I've been doing this for only 4 months (coming from a DE) and recall doing many of the steps you are talking about.

One thing I did, was to alter my pre-shave method. Before straights, I'd apply Poraso pre-shave, shower, leaving face alone, and then go right to lathering and shaving. Now, I do multiple steps. In the shower, I wash my face well with soap, and then apply hair conditioner and let it sit. After showering, I apply pre-shave cream (was Poraso, but now I use Noxema and glycerin) and let it sit while I prepare the lather. Then, I apply a hot wash-cloth to my face (twice) to really heat up the beard. I reapply pre-shave cream and then put lather on top and do a pass. I reapply preshave and lather and do next pass. Since I'm getting faster, I lather in two sections (used to do four).

It seems to work for me, so I haven't altering any of the steps.

The other thing that I wanted to comment on was your mention of less than 1/4 of the blade used. I'm wondering if that is cause the toe to dig in a bit? Maybe you can try keeping the blade totally flat (heel to toe) and at a low angle (1-2 spine widths) and do just a downward pass. Don't worry about trying to get the hollows (I have issues on either side of the adam's apple), or trying multiple directions.

After doing that a few times, try some direct up, and slightly angled up or down passes on the neck, again, not worrying about getting BBS. You can always finish with cartridge/DE, if needed. I (personally) know that is hard, to not want to stick to it and get a BBS shave, but I've found that the more I keep trying the more I irritate the skin in that region (which makes subsequent shaves harder).