Regarding the spell, I can recommend the following – play with a rule that prohibits its use. You'll quickly realize that there are many other spells that are just as useful. As well as combat tactics that are different from "cast mass spell and obliterate everything."
From my personal experience – when building the 2nd tier, I usually look for Blind, not Word. Especially in dungeons. I don't hesitate to rebuild the 2nd tier for Blind; I do it regularly. I rarely do it for Word, and more often for FF, rather than for neutral creatures.