I am using my brand new Focal Utopia with the Chord TT2 DAC and it sounds magnificent. Still waiting for my Lazuli Reference cable. I cannot imagine the combo could sound even better with a better cable, but everyone says that here, so I am up for giving it a try.
Over on the Chord TT2 thread there are many Utopia users who swear by the combo and are confident the TT2 output has plenty of power without the need for an additional headphone amp. That's my experience too. If you have not auditioned Chord DAC technology they use their own programming rather than a third party DAC chip, with some amazing results. It is worth taking the time to check out one of the Chord DAC models before committing elsewhere.
That said, Focal's own Arche DAC/Headphone Amp also seems to be well regarded. I have not heard it myself because I already own the TT2. If I were in your position it would be on my shortlist to try.
Good luck and keep us posted!
The Arche with the Utopia setting is amazing and is a friction of the price of the TT2. Saying that, nothing wrong with the latter either. But if money is an issue, an Utopia or Stellia owner cannot go wrong with the Arche.