I'll begin at the beginning. Shoe-horning this stuff into somebody's else's perceptions does not end well.
In this example though, you're following the logic I'm accustomed to.

My question was why you constructed an up-sloping trend channel based on a supply line instead of waiting for the ability to draw it with a demand line. (In terms of extremes, up-sloping would use low-high-low points, down-sloping high-low-high points.) Put more simply, I thought that the relevant slope angle was that of the side which is overpowering the other.
And the trade off the 1m. I was going to do this myself but thought it would make a nice quiz. Anyone who wants to play is welcome to do so.
Not 100% sure what you're looking for, and I'm still not even half-way in Wyckoff's 400 pages, but I'll give it a shot from my current model for fun, even though my slower perspective will be evident. No laughing!
1. Break out of resistance level.
2. We found some supply.
3. Price retraces to the median line with brief consensus.
4. Test of former resistance as support and of tentative demand line, enough to get me interested.
5. New demand found.
6.
7. Price reaches the median line and the current high again, meets the same supply as before 2.
8. Re-test of the demand line, interesting alternative entry for me.
9. Break through current high, new demand still present.
10. Some consensus found below the upper parallel.
11. New high found new supply, as in 2, and yields a strong reaction. (Note that my normal protective stops would likely be around 1962 and thus get me out here, but I'm trying to keep the above closer to how I interpret "purer" SLA, which would involve staying in through here until the demand line gets broken. Exiting at this break of the median line would be arbitrary to me here.)
12. Price finally breaks the demand line cleanly enough to exit.
Here's an alternative (again roughly drawn in the GIMP, sorry about that, the median line is a bit too high) where I update the channel's slope based on the loose support found at 4 to better encompass the possible up-sloping range at that time (11:00-ish). Interesting how the above illustrates demand a bit better (4, 8, 12) but this slightly gentler channel happened to provide me with the "blue-to-blue" (supply-to-demand) limit exits I'm fond of (at either "10" or certainly "DT").
Again, I realize this isn't pure "draw a straight line", and certainly not narrating much behavior, especially knowing how you hate orders placed in advance, but that's my play since you encouraged participation.

Looking forward to seeing yours! (And to look back at mine in a month or two...)