Why don't custom roms update the radio as well?

[gguruusa]

It's not really that complicated.

There isn't an all-in-one that I know of (Aside form the alltel rom) because you really don't want to flash your radio all the time - it's not the safest thing to do. Since you only have to do it once, the chefs wisely don't see the value in bundling it into each rom release (it adds a lot of overhead). Also, some people like to mix and match roms and radios.