So you are adding in the major 3 to a minor pentatonic. I see.
Let me see if I fully understand.
1. You look at the chord progression and determine what scale contains most if not all the chord tones. That is the one you use.
2. The strong notes you choose from the scale are the chord tones from the background chord. As the chord changes your new strong notes are that of the new chord.
Next question. What happens if there is no background chord being played?
i.e You are playing without a band or a backing track. How would you improvise a melody without a chord progression? Do you just pick a Key and use the scale without thinking chord tones?
Thanks