I must add a condition in your second scenario:
-and if you put MAL as :
(frequency reuse sequence grouping)
S A: 1,4,7,10,13,16,19
S B: 2,5,8,11,14,17,20
S C: 3,6,9,12,15,18,21
then you have to use MAIO as:
This MAIO planning is needed only if your HSN is the same in all three cells. If HSN is different, then any MAIO will do.
On the side, between scenario 1 and scenario 2, which one would you choose, quality-wise ?