November can be an ideal month to visit Boracay Island, even though you'll probably see a few quick rainstorms each week. This stunning and laid-back island is in the Tropics, so you can get a quick cloudburst a few times a week this time of year, but they are easy to avoid and the sunsets that form as the clouds are leaving again are often so gorgeous that it's all worth it.
But again, Vietnam can be a bit complicated for first-timers. Specifically, you need to book trains and tours through travel agencies, and Vietnam’s many travel agencies have a worldwide reputation for being hard to trust. They are all great salespeople but the product they deliver isn’t always what you expected. I spent 4 months in Vietnam and loved most of it, though I think it was much easier as a solo traveler who didn’t have a set schedule.
I like your comment about how “rainy seasons” are almost always overstated. I totally agree based on my own experiences and research, although there are a few places where they should be taken more seriously than others. On my most recent December trip to Bali (2.5 years ago, I think), I spent 30 days there and the rain only became a problem that one time I mentioned. It was just an insane cloudburst while taking a minibus from Kuta to Ubud, and in the end it’s actually probably my best Bali story. Aside from that, it’s very humid during Bali’s wet season, but even that really didn’t slow me down. The thing is, in Bali you are usually on or near the beach or a hotel pool (feeling the breeze) or in your air-conditioned room. Or you might be touring around to see temples and rice terraces and whatnot, and everything is outdoors and beautiful. When it does rain it’s usually over in 15 minutes, but often the rain comes over night. That kind of humidity can be a killer when visiting a city, but for me it’s a small issue on a tropical island like Bali.
This is a huge question and I’d need to know more about your preferences and your budget to answer it properly. But I can give you a short version here. In my opinion, which is matched by many other people, the most interesting and dramatic cities in Europe are London, Paris, Amsterdam, Rome, and Venice. Visiting those would require about 16 days to do it properly because you’d want to spend 3 or 4 days in each city, except maybe only 2 days in Venice because it’s quite small.
There are always those travelers who celebrate the end of summer and the opportunity to don a sweater and take out the wool scarves and quilted jackets. For them, Iceland would be a perfect destination, with a chance to see the Northern Lights and adorable sled dogs. Montreal is another place with a winter chill, and at the end of the month, you might even find an early Christmas market. San Antonio gets into the holiday spirit at the end of November as well. Sedona offers chilly nights and gorgeous scenery, while Hilton Head Island still enjoys autumn weather and activities.
Just came back from Luang Prabang, Laos. Cheap and easy to navigate. If with kids you can do an elephant training camp few days. Airport 15 min from hotels and just 2 minutes to get visa (30USD). Not so much to see, but nice vibe and cheap. If you have to choose between Luang Prabang and Siem Reap, Siem Reap has more to offer, but is much hotter than LP in December.
A charming, historic city to visit any time of year, Edinburgh is especially festive during December. Walking through its cobblestone streets takes you back to medieval days when sheep, cattle, and grain were sold in what is now the center of the city. Today, the Royal Mile includes shops, cafes, and museums. Edinburgh Castle, a must for first-time visitors, dates to the 12th century, with its dramatic silhouette overlooking the city. For those seeking holiday celebrations, the Royal Botanic Garden is decorated with lights, music, and illuminated trees. European-style Christmas markets pop up at Princes Street Gardens and George Street, offering traditional crafts, gifts, food, and warming drinks, most welcome during chilly December. The annual Hogmanay celebration welcomes the New Year with fireworks, food, and festivities. Don’t miss the delicious and ubiquitous fish chowder called “Cullen skink,” and be sure to try haggis, served with “neeps and tatties” — mashed turnips and potatoes. Buttery shortbread and whisky from the country’s more than 100 distilleries are also Scottish specialties. A stay at the elegant and historic Balmoral Hotel will enhance any visit to Edinburgh, and while you’re there, you’ll notice that Scottish actor Sean Connery was a guest, as was J. K. Rowling who finished the last Harry Potter book in one of its suites.
If you book a resort hotel from home you'll probably think Goa hotel prices are much higher than you were expecting, but if you book a family-run place once you arrive you'll still find fantastic bargains. It's probably wise to book a few nights online before you get to India, because it can be incredibly confusing at first. After that you might be able to find a similar place for half the price by just checking around the same area.
I think Sri Lanka would be wonderful for 2 weeks in December. The rainy season typically ends early in December, but even when it’s still going it tends to be quick downpours, as you are no doubt familiar with if you’ve been all over southeast Asia. Still at this point there are very few hostels with dorm beds and not even many cheap budget hotels, but at the age of 30 you are probably happier with normal hotels anyway. Value is quite good in Sri Lanka as long as you can spend at least US$30 or so per night, and hopefully a bit more. Food is also quite cheap in general, although there are still surprisingly few tourist-oriented restaurants in many towns so it feels a bit undiscovered. Just don’t spend much time in Colombo and preferably focus on the mountain areas, and I think you’ll love it.
Since flights to Mexico City from the US and Canada are usually quite cheap this time of year as well, this could be a perfect short cultural holiday. This city has great shopping, dining, and nightlife, and the central historic and tourist districts are far safer than most people would expect. There are ruins just out of town as well, so a bit of everything is available.