Doesn't sound crazy to me.
But, by "crisp" what do you mean exactly? Like "crisp" as in the English version of fried potatoes or something akin to that? If so, I think that could be a good idea or at least worth exploring.
Romaine lettuce seems a bit of an obvious choice, though. Not to mention I never liked using romaine as a wrap because the spine of the leaf tends to be inflexible and break. You could use top third of the leaf, but, it has little in the way of crunch.
What about using another leaf like Butter Lettuce, Bok Choi or Swiss chard? You could even riff on a Mediterranean thing and use grape leaves.
What sort of dip were you thinking on using?
If I saw this idea on a crudite platter, it would definitely get my attention.
Would you post a picture of it when you're done?
Good luck!