Well since we're into July, I suppose I'll add some more speculation.

1) PE upgrade awards become possible
1a) Complimentary DOD PE upgrades for EXP/CK come to an end altogether, or become restricted to high revenue passengers - meaning either EQD or fare class limitations, or restricted to CK only.
2) Upgrade award pricing becomes increasingly variable. More granular than the current structure where there are two prices, one for upgrades from full-fare and one for discounted fares. Different miles/co-pay requirements per fare class, or more fare groupings than just full-fare/discounted. Potentially some fare classes not upgradeable at all. Co-pay approaches $500 mark for cheaper fare classes. If award charts are pulled (see #6 ), these rates become secret. The other possible approach here is to eliminate traditional award upgrades altogether, and simply upfare between the paid coach fare and the premium cabin fare, and charge miles at a fixed rate like $0.01/mile, though that would be such a drastic change on long-haul that they may do this only for domestic flights and preserve traditional upgrades on international.
3) SWU upgrades become single-cabin; no restrictions on fare classes
4) Changes to domestic upgrades, such as:
4a) Treating MCE as a separate cabin, with capacity-controlled upgrades (a la DL) - gulp.
4b) I'm torn whether it makes sense to double down on the 500-mile cert approach and start removing unlimited comp upgrades, or if it makes more sense to ditch the certs and expand unlimited upgrades, but with the introduction of some revenue-based component (such as fare class restrictions).
5) Partner PE award bookings become possible
6) Expansion of dynamic award pricing; removal of award charts is perhaps the logical next step even if no execution happens at this juncture and Saver awards still exist for the time being.
7) Changes (read: increases) to elite qualification requirements for 2020 qualification year.

Again, just pure speculation. What are others anticipating?