Almost every adult in America shaves something. Men shave at least part of their face, women typically shave their legs and armpits. Most new shaving technology since 1930 has been to just put more blades on it.
Some people even insist that the old fashioned way, with a long knife, is better. The knife, unlike the disposable razors, doesn't deform when heated, and experts point out that heat is important for a good shave. I think these people are throwing the baby out with the bathwater. After all, disposable razors replaced knives for most people because they eliminate the possibility of cutting yourself from holding the blade at the wrong angle.
I can think of an immediate improvement. Lengthen the plastic holder, but leave only air in the extra space. When the blade expands from heat, it expands into the empty space, without deforming. This would combine the advantage of the straight knife (doesn't deform) with the advantage of the disposable-type (never the wrong angle, can't cut yourself.)