I did not do a "tour", but instead did independent travel on a Luxury Ship. http://www.seacourses.com/silversea-expeditions-silver-galapagos.html
All cabins (50 of them) were "suites". For the Galapagos, the cabins were extremely roomy.
I had a Deluxe Veranda Suite and enjoyed breakfast on my private balcony each morning.
Each cabin also had "butler service"; as on other Silver Seas cruise ships. And a spa, etc, etc, etc.
As a solo traveler, yes, I would do this "large" cruise ship to the Galapagos again.

Because activity on the Galapagos Islands is strictly regulated by the National Park Service, there was no real advantage (for me anyhow) for selecting a smaller boat.
And for me, there were a lot of advantages to this larger luxury cruise ship with many activity options and true pampering in between.

Excursions groups on the Silver Galapagos were never larger than 12 people at most. Guests were also not unusually rushed.
Due to good planning by the ship, one small group seldom saw any of the other groups from the ship.
So that was no different from being on a smaller boat.
Guides were also Level III; which is the highest level you can get.
Hikes were between 2 1/2 hours to 3 1/2 hours each; with two a day.
Midday, the sun was too intense and it was too hot to hike. Days, however, were extremely full.
In addition to the hikes, there was snorkeling and zodiac cruises and kayaking. Plus a glass bottom boat.
Plus I was given a private tour on a couple of the islands... That's how I got to visit the Cane Liquor Distillery.

I enjoyed the advantages of a plush larger ship and felt no real disadvantages.
During my time on the Silver Galapagos, the ship also had no more than a maximum total of just 60 guests.
Yes, in comparison to a 16 person vessel, that might seem like a lot. But I got to know everyone.
Things were very well done.