Let's just say the Nats reactivated Soto a series too early and could have used Perez for a few more days with the lefty starters lined up to face them.
The idea of optioning Soto after the NYY series has some appeal if he can't play the field, TBH. Option him means not restarting the 10 day minimum you'd need for a DL stint. As you say, the stack at 1st/PH/DH limits what can be done. As it is, if you use Stevenson as a PH early, you basically cannot PH for Robles against a tough righty.