First off, since this this misdirection tree it’s rewritten every Rogue I’ve tried to build. MisTac came be really useful on it’s own, but it just seems right to follow through with MisRed and MisAtt.
About your original statement, however, the only problem (that’s not a problem) is that Misdirection Tactics is just more likely to piss melee characters off, because there’s no limit to how often you can use this feat in a round. ...but that’s it. MisTac surely forces hack-n-slash characters to work harder to hit you, but that’s not really your problem. There are still more than a few ways to cause damage without relying on melee attacks.