So you'll give your opponent the opportunity to fuck you over with a Echoing Truth plus other random Counters they are likely to draw with your their 2nd/3rd turn? Random Therapies, in my opinion, are just as relevant as you view our random "Nice things."
If he draws counters, it doesn't make any difference whether you play Hypnotist or FKZ, you have to Therapy for them before you DR in any case - no difference!
If he plays Echoing Truth (which is really really not played frequently!), he can still screw your tokens away. Again, it won't make a difference whether you play Hypnotist or FKZ (he can play E-Truth when DR is on the stack but you already have your tokens) - no difference!
Except that you will win immediately if DR resolves, Hypnotist is one or 2 turns slower. And I guess it can be very relevant if he draws 2 additional cards or not.
Just as I and a couple other people in this thread have said before - Mathematically, it is harder to come back from a Turn 2 Mind twist than it is a couple of random Therapies. Your opponents can mise outs against Hypnotist just like they can against Flame-Kin; but in my testing, there are fewer outs to Hypnotist than there is to Flame-Kin, and thus my reason for running the Hypnotist.
That's is really not true. The cards you don't Therapy for are irrelevant (such as non-counters and non-carddraw) and useless for the opponent against you; discarding them as well with Hypnotist just changes NOTHING about the odds of his topdeck or whatsoever. It really doesn't.
And concering outs against them, it also makes no difference. The only difference is that you can stifle FKZ to prevent the Dredger from running you over, but you will win next turn. But If you play it correctly, the amount of outs won't change against either FKZ or Hypnotist.
Just to recap the point I mentioned above:
When you Dread Return your creature, it goes as follows:
1) Sac 3 creatures
2) DR on stack targeting FKZ/Hypnotist
3) Bridges go onto the stack
4) Bridges resolve, you get tokens
5) DR resolves, you get FKZ/Hypnotist, you win or mindtwist.
Between step 4 and 5, the outs you mentioned against FKZ and Hypnotist are equal as the opponent can cast E.Truth, pop EE or Powder Keg and so on... The only difference I can see is that FKZ can be stifled by some random fishesque decks (which don't see much play as well).
I'd really run more real stuff instead of cute stuff. My maindeck is already stuffed with disruption, I guess DR should be the card that either ends the game or saves your ass from annoying stuff (-> DR for Angel of Despair for instance).
edit:
I have to say this again, Hypnotist also blows against: Mystical Tutor, Vampiric Tutor, Sensei's Divining Top and Imperial Seal.
Mystical and Vamp played in response to Hypnotist is like "Hah, fuel my graveyard, I'll Yawgmoth's Win now", Imperial Seal is like "You should better win NOW!" and Sensei's Divining Top is like "I can still dig for my bomb to blow you out of the water, wait for it!"