1. M2 for edges and Old Pochmann for corners.
2. I average around 3:30-4:30.
3. I don't think sub 1:00 is even hard for some people with this method, but I don't know what the limit is.
4. I recommend Old Pochmann for beginners, M2 for a quick improvement, and BH for advanced solvers.

I don't think index/ring would be much slower than index/middle for me, and I can stream around 180bpm pretty comfortably. The only problem would be one-handed trills.

Line 3 was EO because I'm too unfamiliar with much else from a 2x2x3.
Line 4 and 5 might as well be one, and I'm not sure why I kept them together. I think you're right about the 4 corners; that's what I had when I started looking for insertions. I'm not sure where my R went :P
Forgive me if I...

Tried FMC for the first time today. It's hard!
R L U' L' U2 R' L' D L' R U' R2 D L B' U2 D L F R D U' B R' D'
U' L' U B R' L' D' L' (8)
R' U R2 F2 (12)
U' B U' B' F R' F' (19)
R' U' R U R' U' (25)
U' R U2 R' U' (30-1 = 29)
I then spent 15 minutes looking for insertions which ended up messing...

I had a math competition today and one of the more difficult problems was this:
Find the sum of the coefficients of all odd powers of x in the expansion of:
(x^2 + 2x + 3)^3 - (x^2 - 2x - 3)^3

A B9 is an 8 mover with a setup where the setup cancels with the interchange. An A9 is where it cancels with the insertion. I'm pretty sure, for corners, that they're never optimal.