Quarter-inch is in my amateur opinion rather thick for the size blade you have but it's what you have so it's what you use. Maybe a hollow (concave) grind would be better to deal with the thickness but I've never done a hollow grind personally, only flat grinds on my Sears 2x42. What sort of grinder do you have to work with?
Regarding the design, you have a right-angle inside corner where the bottom of the handle reaches the ricasso/blade. This could be a place where a crack could start during the heat treatment process. You could could change it by rounding it up into the handle area, making a finger grove.
#1 The top image is the profile you made.
#2 shows the suggested rounding and finger notch.
#3 shows what it might look like if you changed the dropped point a little bit in an attempt to make the lines flow better.
#4 shows it with an extra half-inch added to the handle.
Hope this is of some help.
- Paul Meske