Should I offer a cocktail menu at the bar?

I also vote for one cocktail you can make in advance, along with something fizzy, another wine, and beer.

Yup, I vote for just one simple elegant cocktail...

I agree with having one signature cocktail. simple and elegant.

Wine, beer, champagne or prosecco and maybe a premixed cocktail in a big jug or two. Or three. However, I also have a bottle of bourbon, vodka, etc. on hand, if anyone really prefers - I just don't put them out on the bar, so they're not the default. Also OJ, cranberry juice, tonic, etc. for both non-drinkers and those who really crave, say, a vodka tonic. Big bowls of cut up lemons/limes too. I leave anything involving an entire menu to the pro's.

I'm with HLA and SKK, no menu offer a few mixed drinks, wine and beer.

I prefer to serve a signature cocktail or two. They can be batch mixed, so no one has to spend a bunch of time mixing individual drinks during the party. If I wanted to have a cocktail menu, I'd hire a bartender for the party.