Once Falcon Heavy is flying you could upgrade those flights to FH with a flight profile where you can land all cores on land. The only difference would be more fuel used (which is cheap) and threefold increased risk of stuff going wrong in the first two minutes. May depend on how important it is to get those cores back immediately. Upgrading otherwise expendable flights to FH is already planned as well.

The upgrades of Block 5 later this year will improve reusability and performance, though, so more missions can be RTLS.