Brett,
Yes, that's the spot. Your first stem flairs out of the C scroll, and up to just ahead of the forward extension of the butt plate. That line is pretty much okay.
You next stem flairs out and heads to the upper corner of the butt plate. The flat area is just where the stem leaves the C scroll. Your stem that goes down toward to toe of the stock shares the same flat spot.
Someone here suggested using a French scroll to lay out the basic backbone design, and I think that's a good idea, to help you master the flow and curl of the C and S scrolls. I bought one some time ago, made of thin clear plastic and quite flexable.
One thing, at least from my perspective, is that C and S scrolls need not be exactly symmetrical,,, as long as the lines keep curving and bending, your eye won't generally catch it. But as soon as the line goes straight, or the curve turns into a kink, the eye jumps right on it.
Like I said before, I like your design. I think it fills the area well, has a nice symmetry about it, and like the little flowers/leaves on the tip of the stems. As for the leaves along side the stems, you could vary their size a bit as they travel up the stem, or put them closer together to give a little different affect. Once you get it smoothed out, I think the design would look really fine on a rifle!
If on the other hand, you really want to do a Joe Long impression, copy the design elements of the gun in the library because that's first class Joe Long carving.
John