I don't think tiramisu is a bad coffee flavor (on it's own) although to make it palatable (to me) I added some cream, a bit of sweetener, and some merengue. It had to steep a LONG time, that seems to be the case with many coffee flavors. It's not exactly coffee once I added stuff to it, but it has a lot of "coffee notes."
Depending on the type of coffee you want (cappuccino) you might do well with an espresso type flavor (I can't recommend one specifically I haven't spent a lot of time with coffees) and maybe some milk/cream notes and if you add sugar to your cappuccino, well, there's a brown sugar flavor made by someone but it might be useful as far as your recipe, or you could just use a sweetener as an additive. Best of luck,
Anna