He wanted to have more control of the tip when it was upside down where you lay your index finger along the spine. It made sense, but I hadn't seen/heard of that before!
For the handles, I do either a full tang with the steel showing all the way around the handle (which makes it heavier, but I can also drill out the tang to lighten it bit) or do a hidden tang. Hidden tang is MUCH lighter weight wise! The biggest one with the funky handle is less than 5oz for the entire blade, even though it is almost 10" overall length. I also like using 3/32" thick steel for hunting knives; it is thinner and lighter and makes for a very slicey blade! I do full grinds (flat and convex) and put a taper in towards the tip, so it brings the weight back towards the hand. For the hidden tang handles, I try to keep the tang around 1/2" wide for strength and then cut a piece of G10 or Micarta material the same thickness as the tang to fit around the tang and then attach the scales to it.
In the green/orange pic, the orange G10 is the spacer that goes around the hidden tang and the green is the micarta scales on top. I usually do a coke bottle shape on the handles like that one or do a taper to the front and back of the handles so it's a tear drop shape, depending on the shape of the handle itself and use of the knife. Kitchen knives get a mix where it has a straighter taper to the front, some palm swell and then a smaller dip in the rear of the handle like the blue pic.