That sentence is unclear to me, too. I understand it like this:
C'est déjà ça = c'est mieux que rien = it's better than nothing
en vrai = en réalité, en fait = in fact, actually
"It's actually better than nothing." That sounds a bit odd however, whether in English or in French..
As for délire, it doesn't mean delusion. It's slang and pretty hard to define. Basically it's the activities done by a person, implying they're silly. L'oncle Soul's délires are music and what he does in his private life.
I can't quite understand what he means by "Mais je sais qu'en vrai c'est déjà ça," but "I know it's already that," sounds very bad to me (as a native English speaker).