Is not easy to manipulate the Automated Placement Engine behavior, but you can try assigning a Data Defined Priority placement, based on the content of one field:
Select Edit in the Data Defined Priority menu and write an expression.
You can calculate in that expression a value between 0 and 10. Or you can refer that expression directly to a field, manually or with an expression populated:
(("presion" - minimum("presion"))
(maximum("presion") - minimum("presion")))
In my case 'presion' is the name of a field that I want to use as priority.
With that expression, I am assigning a value of 0 to the minimum, a value of 10 to the maximum, and a linear interpolation to the others.