FYI, the blur de-assists very well, it has a nice detent and is actually much smoother with the torsion bar removed.
The leek, not so much, weak detent, doesn’t flip at all, and the stump studs are hard to get to, just doesn’t work well with spring removed, but I prefer the blur without spring.
My only gripe with the blur is the pocket clip, it’s just not big enough to clip well over the seam in my work jeans, but it’s the same as the leek clip, so if you like the leek, you won’t be bothered by the blur.
I’m not a fan of tip down, I do agree with your opinion of spydercos with the hump being pocket hogs however. The native series doesn’t suffer from the hump problem and carries well.