Just be careful with the whole 'marketing' thing. The #1 reason I spent money on this game was the fact that I didn't feel at all pressured or manipulated into doing so. It was a very refreshing change from 99.999% of the other billion or so online games floating around out there. That was also the reason I didn't mind when just after spending $25 on the Basic Edition, it became available in a bundle for $12. That sort of thing happens too often though and people will get resentful... and possibly stop contributing directly to the game, waiting for outside deals instead.
Yes, marketing well is a very fine line. Having sales though doesn't really make people become resentful -- at least not significantly enough to be detrimental from anything I've ever encountered. Being pressured to buy is bad, but simply having sales shouldn't give any pressure outside of some minor time sensitivity.
The Celestial figures were put on a 50% off sale the second time the Celestial boards were used in ranked MP. That's the only figure sale I remember (I'm not counting the sale on Basic Edition figures at the end of beta, since they were lost when the game reset for release).
I wonder if they went on sale because those figures in particular failed to sell well. Reminds me of AD&D Oriental Adventures. Maybe it's just that kimonos and samurai helmets have a hard time mixing with an otherwise vanilla fantasy setting.