What about the case of take-off, rather than arrival, where a performance loss is suffered and manoeuvring is required. A 10nm MSA allows one to stay within 10nm, at or above said MSA and manoeuvre to one's heart's content.
Some 10NM MSA are lower than some of the 25nm sectors, some are higher than the majority of sectors; eg CS NW 5200', NE 4000', S 6500' BUT 10nm 5600'.
Or, one can assess which sector one is and apply that MSA.