Sizing half the neck is just fine, and not a problem. Actually, it's an advantage over FL dies.
Bushing dies do not FL size necks because of die length, but because a supporting land is needed for the bushing.
Cutting a normal bushing die down won't change anything there.
Now if you really want to FL size necks(for some reason beyond my understanding), you could get a custom die with a combined shoulder/neck bushing. These are threaded dies though, and custom FL dies would function the same & cheaper. With both you lose the advantages of inline/bushing/partial neck sizing, in exchange for added body sizing.
Another option is a bushing bump/body die, lately marketed as FL bushing dies. Again, threaded(not inline).
If you'll accept that partial neck sizing is all needed, then a Wilson will work for you as well as it works for everyone else, and you can body/bump/neck expand with threaded dies as separate operations.
The reason I suggest FL sizing necks is a horrible plan, is because it brings a donut into tension variance that otherwise wouldn't come into play. This action, increases runout, seating depth variance, and you lose chambered case centering.
On the flip-side, I cannot think of a single advantage in FL sizing necks.