[thejeff]

Astral on the pretender is risky, but can be very useful.
Astral bless can be nice for some nations. Some of the immobile pretenders can get to S9 fairly cheaply, which pretty much eliminates the magic duel worry. High S levels allow for easy first round Mass Enslave attacks.

Lower levels of Astral are really nice for nations with little or no Astral magic. Forging Rings of Sorcery/Wizardry is one of the main keys to diversifying.

I also think the danger from Magic Duel is overstated. It's a threat certainly and really low levels of S should be avoided. With S5 or S6, anyone but nations with high S mages or cheap S1 mages aren't really a threat.