@Packerjohn - this would be a very good place to start!
https://www.expediacruises.ca/en-CA/400003
Booking with a travel agent will not cost you any more than doing it all yourself (they get paid by the wholesalers who own the properties or the cruise lines). This example above is only one that's in your area; there's likely another one or two close by as well. They
specialize in cruises and can provide a wealth of info. for you and your lady to consider. Be specific with them on your likes & dislikes so they can better guide you to the right ship & itinerary within your budget.
Go for an exploratory meeting with an agent; face to face. Tell them what you are looking for specifically and ask about options, You'll get lots of things to consider and you can go home then mull it over and decide later to book something or not. There'll be no high pressure to book something right away although, I would do it ASAP as most winter cruises will be close to fully booked by now for winter 2023-24.
Mid-range cost options for seniors, Holland America ships are perfect. There are others too but the really nice ones Regent Silver Seas) will get real expensive real fast. I agree, Celebrity Cruise lines is over rated IMO. I do like Oceana a lot but they are a bit upscale price wise. Princess is another decent mid-range priced cruise line.
Tips to keep your blood pressure in check when booking a cruise:
Pick a cruise of 2 weeks or more (parents don't tend to yank their ill behaved offspring out of school for more than a week or so).
Don't cruise around Christmas or March Break.
Pick a ship with a capacity of 4,000 or less. These tend to be the older ships not the newer 6,500 monstrosities.
Oh yeah ... don't book a Carnival ship

no matter how attractive the price may be!
Forget Med cruises in winter or European river cruises. The cruise lines all 'reposition' their ships in the fall from northern hemisphere to more southern locals. The reverse happens in the spring each year. Alaska is May - Sept. only pretty much.
For my money, I always book a balcony cabin. Yes you can save money booking an inside cabin or a 'window' cabin on a lower deck but nothing beats ordering a carafe of coffee to your cabin when you wake up then sitting on your balcony and watching the ocean and the world pass by before you head for breakfast. Southeast Asia could be an option or other spots in more southern areas in that part of the world.
Panama Canal either full transit or partial transit (I'd go full transit). South America, including the Amazon. South seas, Tahiti , Australia/New Zealand. There's all kinds of stuff around that region.
Start with a good Agent and go from there!
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