Good to see you here!
I’m not hearing anything intrinsically wrong with the vocal.
Kevin sort of lacks energy, but I think that’s the nature of the recording, not any fault of your own.
The range is a bit low for Kevin, and that probably doesn’t help either. It’s trivial to change the of the singer with SynthV, just go to the Voice panel and move the Key Shift slider:
Of course, that won’t change the pitch of the instrumental, but you already know how to do that in BiaB. You can mute the instrumental track and move through the different keys, looking for a range that might suit him better.
Especially when a singer is holding a note, you want something to happen. So go into the Parameters and pick a parameter by clicking on Edit:
Base Parameters or Vocal Mode, it doesn’t matter, just start with something:
The in the Piano Roll pick the Pencil tool:
Now draw a curve in on the Parameters:
Did that help? No?
Then erase the prior curve (draw with Right Mouse Button to erase), choose another parameter, draw a curve for it, and see what happens.
Basically, play with the parameters to hear what they do, and you can give some extra life to sustained notes.
You can also make global changes to his voice. In the Voice panel, play with a mix of Vocal Modes. When he’s in the low register, you can use Tone Shift to use samples that originated from a higher register for a different timbre.
Also, you can open the AI Takes panel:
Then select notes, and change the Expressiveness and Enhancement of the Pitch, and adjust the Timbre of those notes:
Didn’t like the result? Undo, change the parameter, and try again.
Hope that helps!