As a wedding florist who solicits photos for promotional use, I have looked at hundred of thousands of wedding photos, perhaps millions, from dozens and dozens of photographers. Some of them are companies employing several shooters, others are small teams, couples, or solo artists.
DWU2 has given you a great list of questions for candidates, although I wouldn’t fuss too much about what equipment they use.
Check their websites, and get a sense of their style and feel. Break it down by category- prep, ceremony, formals, candids. Get a sense of what’s most important to you, and convey that to your candidates.
Our best clients come to us from referrals by other vendors. There are always instances where a couple brings in a photographer, caterer or band from out-of-state, but for the most part we all work with each other very frequently. Ask your other vendors for recommendations, and ask why they are recommending them.
Lastly, meet them in person and find out who you connect best with. And while you don’t want to micromanage them, be sure that they understand why you chose them and what you want.
Hopefully budget won’t be an issue!

The only circumstance under which I would even consider trading the 70-300 for the 14 is that the 70/300 is literally collecting dust. Ultra wide can be fun, but is specialized and not well suited for what you intend to use it.
FWIW, you could probably rent the 14 for a little more than the price difference of your trade.
If you don’t own a more suitable lens for the task at hand, perhaps a 3 day rental of a wide or normal lens is the answer, employing Gene’s suggestion. I’m assuming that the reunion shot is all adults, capable of staying still for 2-3 shots. You’ll want a tripod. Especially if you decide you want to jump into the shot.
You don’t mention if you use your 70/300 frequently, rarely or never.

I'm sorry, what is the problem?

First digital was in 2005.

A relative had just finished helping redesign our company website. Shortly thereafter, a package arrived- a Nikon D70. He told me that we needed to create a portfolio of our work, and to learn how to use the camera and just keep shooting and shooting. And when I thought I had enough photos, to shoot more.

Made the jump to full frame in 2010, a D700.

For now, I'm using with a D7100 and D750. Sold the D70, still have the 700.

Wanna trade???

Yes, I can see why on that type of cruise a long telephoto might be useful.

Here's a thought: Bring two cameras, one with a good tele zoom and one good compact. Use the long lens on the ship and bring the compact ashore.

To address one of your specific questions, the more I shoot, the less I use my 28-300. I loved it at first, and perhaps mine is not a good copy, but the quality negates the versatility.
Seems to me that the majority of the other responses emphasize the need for shorter zooms if you go with one of the cameras you own, unless you want to invest in a solid compact with a good sensor.

Not to mention burst mode!

Several years ago, I was given the opportunity to be a 'second shooter' for a photographer friend whose spouse was out of town for a job they had taken. It was at that time that I learned that I am not comfortable getting right in peoples faces and taking pictures. Candids and posed shots did not bother me, I just found it uncomfortable getting up close to people and shooting.

Great photos, Tim. A good friend of mine has had several books of his photography published; your style reminds me of some of his work from the streets of Italy.

Is this a joke I'm not getting?

Nothing wrong. Enjoy.

doubtful

Don't confuse my lack of appreciation with misunderstanding. I understand him completely.

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