Mathematically, assuming an average block time of ~10 minutes, there are a maximum of ~104 difficulty adjustments over a 4 year period, so even if there was a .01 MB increase at every difficulty re-target (the chances of which are negligible), the base blocksize would still only be ~2.04 MB after 4 years.
Is this a compromise most of us could get behind?
For me, maybe
But bear in mind, saying 2.04 MB after 4 years conceals the fact that the real total blocksize would be 8.16MB when you include the signatures in the witness blocks, Segwit is a part of this deal you're proposing.
if there was to be a hard consensus to move to dynamics.. then its much better to use that oppertunity to unite segwit AND native keypairs in the same area.
EG 4mb for both native and segwit to sit in, in a single merkle block. then have it increase by x% a fortnight.
people running speed tests know that on current modern baseline systems (raspberrypi3) and average internet speed of 2017 along with all the efficiences since 2009 (libsecp256k1) have revealed that 8mb is raspberrypi average home user safe..
so starting with a 4mb single merkle block would be deemed more than safe.
and remember
even with a 4mb rule DOES NOT mean pools will make 4mb instantly..
just like they didnt make 1mb blocks in 2009-2014 even with a 1mb allowable buffer..
pools done their own risk analysis and done their own preferential increments below consensus.