It's a crossover of your appreciation for beers. It sounds like you're used
to super hoppy beers, so it makes sense that you'd be more comfortable with
the more bitter cocktails. If you haven't had a Negroni yet, I'll suggest
trying one - if you like bitter drinks, that is pretty much the end all, be
all of bitter drinks.
If you want to expand your palate, I'd suggest working with rums, tequilas,
and bourbons in that order. You'll know where to go once you adapt to
cocktails with those base spirits.