A lot of work for an original Happy Hacking keyboard with crappy membrane switches.
Oh, for sure. How about doing it with your SMK-88 or something like that? Combine it with etching your own PCB and you could design your own perfect keyboard. Place all your keys exactly where you want them, modify the height/angle on the keycaps to fit your typing style, etc. It'd be a significant amount of work, but you could have
exactly the keyboard you want.
Myself, I'd like it if the outside keys on my 'board were taller than the inner ones, mainly because my pinkies are >1" shorter than my ring fingers, so I have to 'roll' my hands the outside when I type with them. A 'cupped' keyboard top would, I think, be more ergonomic for me. Actually, watching how I type, a W-shaped top, with the FGHJ columns raised slightly, and the CAPSLOCK A ; ' and to the right columns raised quite a bit and angled in would mean much less motion for me.
Of course, I have to admit that making that would be a truly excessive amount of work (and $) to reduce my typing motions by 5% or so...