Not and be compatible with the OpenPGP spec. You can define a safe subset of OpenPGP with some additional restrictions (like no weak keys) but that won't be PGP any more, it'll be a new protocol.
Technically true and it would certainly avoid a bunch of confusion if the new subset carries a new name. However there are a bunch of "OpenPGP" implementations out there but when you start comparing them, it's obvious that they differ quite a bit.
