My work holiday party is at a large Chicago museum, on a Saturday night. The invitation calls for cocktail attire. I have 3 options 1. Charcoal suit. 2. Navy suit - it has plaid, but from 5ft+ feet away it looks like solid navy. The pattern is all the same color. If anyone is familiar, it is one of the BB Suiting Essentials fabrics. 3. Navy blazer with pewter buttons + whatever pants. None of these scream "get drunk at the museum with a bunch of accountants" but what would be my best options? Tie/pocket square/shirt are open to suggestions. Is a v-neck sweater an appropriate addition?