I love fly fishing wet flies, and I agree that the secret is getting the flies to the correct depth.
I fish a three hook set up with a anchor fly that is weighted to keep the tapered leader taunt, along with two side lines for the other two patterns. I use a furled leader, and can insert the side sweeping lines where ever I wish on the furled leader.
Speaking your knotted leader line, I do not know where people get their section measurements, but for a balanced parabolic knotted leader that is better balance with a constant percentage taper I crunch some numbers using Dave Ulmer (Slicfoot) "Big Leader Formula)
You have ..
.022 dia - 32"
.020 dia - 18"
.017 dia - 11.5"
.015 dia - 8"
.013 dia - 7.5"
.012 dia - 8"
.010 dia - 8"
May I suggest that you use a....
.022 dia -30"
.020 dia -20"
.017 dia - 15"
.015 dia - 11"
.013 dia - 8"
.012 dia - 5"
.010 dia - 4"
I would use my calculations, using the Dave's formuala. if I still did knotted tapered leaders.
I converted Dave Ulmers Big Leader Formula over to Furled Leaders, and it is only 25% as much number crunching. The construction of the furled leader takes longer, but is simpler in construction.
Currently I am writing a book on furled leaders; 5 peg, 6 peg, 7 peg, & 8 peg layout versions. So when I have it finished, I will offer it to FAOL for their (free) use.
Parnelli