I think Dann has gone down hill recently, seemingly around the time he got the captaincy. As you say doesn't seem to be vocal enough and doesn't strike me as a leader on the pitch.

Delaney in a heartbeat

Seriously I'd go for Punch or even Wilf. Both local lads with an affection for the club. Both get stuck in and work their bollock off for the team and both are vocal. I think at least one if not both of them are more than capable of rising to the responsibility.

"We love you Palace, we f@cking hate Man U, We love you Palace, we hate the brighton too, We love you Palace we play in red 'n' blue, so f@ck you, and you ...

Gung-ho heart; arm-around-the-shoulder; the quiet word-in-the-ear to pick up players' spirits:

Damien Delaney every time.

Isn't that because Super Al has got rid of most of the alpha males....?

McArthur? Vocal and a 90 min player.

Its a big fat yes from me.
Dann has become less vocal since he got the armband. Delaney is also a leader on the pitch.

Someone suggested Wilf and Puncheon earlier? Sorry but wuld rather they focus on there own games and Wilf does tend to throw a tantrum now and again. Both actually need a leader to gee them up and calm them down at the right time in games.