Those necks are also twisted - they weren't intended to be that way, but it's just how it works out - some necks twist a bit one way, some the other way. You're concerned over .08 mm twist on your Ric, when you have other basses with about 4x that much twist - those are the ones you should be reacting to.
Roasted necks are more consistent (with less twist); what you are describing is just the way wood moves. I generally like to avoid (if the thing plays OK) dressing frets until after a neck has a couple winters under it's belt - you can compensate a bit of this stuff with fret dressing, but if you dress the frets on a new neck, when the neck moves, and you dress them again, you're just taking off fret height that you don't need to. After a few years, most necks become much more stable.