I feel the Hymn to Tourachs are powerful and the only reason why you feel this deck has several identities. The reason why I added them was there potential for card advantage.
After playing the deck many times Im confidant that 6 efficient creatures are effective at winning a game as one resolved Serra Avenger usually will win a game.
I'm kind of curious why you would choose Path to Exile over Condemn?
Negate I feel is a good choice in here. your games are going to be long and drawn out with spell pierce/snare they will have mana to cast bigger spells. Negate is cheap, fills the purpose. I have enough targeted threat removal in form of condemn and swords.
There are two reasons that I don't like Hymn to Tourach in this deck. First is that you have so much control already in on-field removal and counterspells. Why splash a bit of discard in there? Which brings up my second point, if you are truly that concerned about what they have in hand then Duress' or Cabal Therapy's would be a cheaper and more effective alternative...why leave something to chance when you could choose instead. Honestly I would cut black altogether and go blue and white with Meddling Mages. To answer your concerns you are establishing a potential for card advantage with Jace, Ancestral Visions, and Esper Charm's, you really don't need Hymn to Tourach, again I suggest cutting it, or if you are in love with what it does then replace it with Duress' or Cabal Therapy.
If you are happy with your 6 creatures then that is fine. I won't tell you otherwise. I will warn you that your only real wincon is killing via creature damage, if the other player has enough removal or counters, then you are in trouble with only 6 creatures in your deck.
Path to Exile over Condemn is simple.
1. You are removing the creature from the game, not putting it where it can be found again (via shuffle or search) - that is HUGE.
2. You are giving a land to them instead of life; with all of the control you have life is more dangerous than additional lands.
The problem with Negate is that it is limited. I play a lot of casual race decks like Elves and Goblins and Zombies. You would be in trouble with a Negate in hand against any of those decks.
Again it is a casual deck and with that in mind it looks pretty good, but it can be a lot better with spending very little money. Maybe a simple addition for some of your removal would be a few life gain cards to offset some of your shock lands.