Hmm.. yeah at first I wanted to do something like that, but it would be a pointless ability. Actually the only attack that does use mindaccesing skills, is Headache. If you read the description, it says that the mindreader uses his skills to give the unit an Headache causing damage.
Furthermore, the mindreader doesn't uses his mind really much (hèhè..), but that doesn't take away that the other abilities aren't good.
Of course anyone could have his opinion about the hero, and he's free to comment of course. But personally I have never seen an ability that slows time (actually it slows the units.. but that's not the point). Also the Mana Transfer abilty could be used in strategic ways. If you cooperate with other heroes, you could save some mana. When the other hero ran out of mana, you can replenisch it. And of course if the Mindreader runs out of mana, you can replenish his mana too. It is possible, but only stupid people would do this, to add mana to enemies.
And the Crazy Minions just add a bit of fun to the Mindreader, because I just think they look funny

, and of course they aid the Troll in battle, proving themselfs usefull.
--EDIT--
btw this isn't a spell, this is my entry to the Hero Contest