I have a parcel database of about 16,000 in an SDE database on ArcGIS server. Other layers there edit more quickly. On Monday of this week, everything was fine. Most of the time it takes 20 to 30 seconds to select a new parcel to edit. Once it is selected, editing is fine. Using ArcGIS Pro 2.0.
when was the last time you did geodatabase maintenance? like compress -> rebuild indexes -> analyze datasets?
also check your spatial indexes. if they don't match the data frame that can affect speed.