Is there a particular reason you're looking at twins for that mission? There are singles that will meet all of your stated requirements, so a twin is only going to be the best choice if you have other requirements beyond what you have listed so far. Here are some mission parameters that I would be thinking about before choosing a twin:
- Does the passenger want to sit next to the pilot the whole time or spread out in club seating to watch movies, read a book, crochet an afghan, etc.? (Baron 55, Piper Aztec, and Cessna 310 are fine if people like to face forward. Seneca or Baron 58 will be a better fit if your passenger prefers club seating.)
- Will you need to dispatch into IFR over mountains where the MEAs may require pressurization or oxygen? (A pressurized twin might be out of reach for other reasons, but a pressurized single could be a good substitute.)
- What hangar options are available to you? (The Twin Cessna tip tanks take you out of a lot of T hangars. Wingspan, length, and height of all twins will be a factor.)
- Will you ever have to park outside in cold weather? (Preheaters for two six-cylinder engines will cost a lot more than for one.)
- What local maintenance options are available to you? (Don't buy a super-specialty plane if you have to rely on the plane to fly itself 1,500 miles to the nearest experienced mechanic.)
- How much multi time do you have? (May make you uninsurable or bankrupt from insurance premiums in any but the most basic twins.)
- Are you able and willing to spend your annual vacation time traveling to attend recurrent simulator training? (Mandatory in most cabin-class twins.)
The best certified plane for your mission could be anything from a Mooney up to a short-body MU-2. Therefore, you should obviously just get a Bonanza.
More seriously, the "get a Bo" response has a lot of value because it is a really good plane from which you can measure all others, and then make an objective determination of which plane best fits your mission.