I agree with your points. But I should probably explain something. I'm sure making the template by ones self is completely doable. But when I did my own template, I was definitely struggling. Not only did the hairline come out not what I intended, but the shape, contour and fit was suspect as well. I couldn't put the template back on my head without having to press down hard to make it conform to the shape of my skull. I knew it was off with respect to accurately representing my skull shape. The saran wrap was initially nice and snug but as I kept putting on scotch tape it kept changing its shape. I was frustrated and didn't even bother considering trying again since it took me hours to make it. That being said, it's one of those things that would require practice and repetition, to make it accurate and precise. And some things are best done by another person, especially something that involves one thing we all can't see, our heads, like haircuts. Getting it done by someone else who's done it way more than I have could be more beneficial. Since I probably screwed up, it might be best give someone else a try.
About the system behind hairline, I guess I won't ever know till I try right? I know my old hairline wasn't as dense as this one but this is a non graduated system. And I personally think it could work. I only say this because my hairline wasn't the the giveaway for my hair loss, it was more the rest of the top area, and a graduated system behind it could blend more easily. If not, I guess I can thin it out a little more or order a lower density at the hairline or overall. I just don't want to ignore a potential benefit if it's there.
As far as the attachments go, that's one thing I need to learn. I need a system undetectable as possible to touch and sight. My problem right now is visible lifting throughout the perimeter, visible lace, visible glue, white glue on the lace, gaps between the tape, I can feel the edges of the lace too. Also what's the difference between lace release, glue melter, and solvent.