How about raising it a level? Would that solve a lot of your issues?
As for somatic components, very few spells are verbal only. Maybe 10%. A lot of them aren't very combat-optimal.
I would first take a look at it in comparison to Tenser's Transformation. If you are getting BAB = level, then that is the bulk of what Tenser's does (and Tenser's doesn't allow ANY spellcasting afterwards). If it is weaker than Tenser's significantly, I could see having it be one level lower, but if its just a flavorful version, it should be the same level or higher (depending on how much better those extra modes make it). Personally, since Tenser's gives other bonuses, I think it would be balanced at the same level, but not any lower.
I was wrong when I said many spells are verbal only. My intent was, its easy to get around that restriction by using the Still Spell feat (especially for sorcerers).
You're right, you outlined what "crime" means with regard to the spell, but it *is* still confusing IMO because the spell is called "Detect Malice" when it actually detects a subset of what someone may think of as "crime". I guess I just can't see a ward that goes off when people are planning criminal intent (seems like more of a modern rpg thing, not a medieval concern). YYMV (and probably does).
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