Here's a link to the joint press release, as issued by MLB and the MLBPA (note: .pdf file):
One thing that jumped out at me: Beginning in 2020, active rosters in September will expand to 28 (which we knew) - but that's no longer discretionary; the release says "From September 1st through the end of the championship season, all Clubs must carry 28 players on the active roster." (Emphasis on the 'must' added by me.) No more waiting until the AAA post-season is over; the Active Roster minimum (which increases from 24 to 25) goes to 28 on September 1st. So some kids on optional assignment will be getting a cup of coffee, even in organizations that might otherwise not do that.
With regard to "two-way players" - To qualify as a "two-way" player, he has to have met certain minimums, either in the current season or the prior one.Upon reflection, this could work.
First, there's no restriction on using pitchers as pinch-hitters, or as DH. So a pitcher who hits well enough to be a "two-way" player can qualify by starting as a DH in 20 games...not an unreasonable hurdle, and realistically, clubs aren't going to want starting pitchers playing in the field... but DH? Sure. (This argument assumes a universal DH - but that decision is clearly coming.)
Second, for a hitter to be designated a "two-way player," he needs to pitch in 20 innings - in extra-inning games or blowouts...after which he'd gain the "two-way" designation and be available to pitch in other situations. Again, if the guy's good enough that you want him to pitch (as opposed to need him to pitch when everybody else is unavailable), that's not a tremendous hurdle.
Also - not only is the DL for pitchers increasing from 10 to 15 days... so is the minimum time a pitcher must stay on option if optioned to the minors. No more optioning a pitcher to AAA when you want to skip a single start. I might argue they should increase this limit to 20 days - which would guarantee that optioning a pitcher in this way would always burn an option year... but that's just me.