It sounded like you wanted to go big so I’m not going to list domestic options.  There are plenty of good choices in the US though if you decide to go that direction.  Namely, we’ve enjoyed Hawaii both times we’ve been and there is so much to see in the Southwest.  Either would work in the winter.

With that said, here are the places that stand out most to us.  I’d encourage you to look at my Facebook albums.  I try to write the descriptions to provide some basic info on the locations so you could recreate a given trip.  I don’t know what kind of travel you enjoy but can give you more info on any trips that I don’t mention here.  We prefer adventure travel that keeps us moving and we don’t mind roughing it a little.  Just because we do that, doesn’t mean that’s the only option at any of the places I list.  Also, we lean to mountains over beaches.  Anyway, there are the disclaimers.  This is a bit of a downer but January is a tough month.  It’s too cold most places and in the Southern Hemisphere it’s too hot.  Onto my picks…

Unforgettable – Namibia

When:  May or later

Length: 1.5 weeks+

Namibia is a great introduction to Africa (I say that having not been to any other parts).  It’s safe, a budget option (aside from the plane ticket) and fairly untraveled.  We went for 2 weeks and explored on our own.  We rented a truck with a pop-up tent on top.  We slept in the tent about 2/3 or the time and in nicer places the other 1/3.  The trip was less than $3,500 but we kind of cheated by using points for the flight.  You can see the full budget breakdown here.  If you want a fancier and expensive option, look into Botswana.

 There is so much to do whether you want to be active or take it easy.  The Namib-Naukluft National Park is, in my opinion, one of the most incredible places in the world.  It’s in the west and features huge sand dunes and the one of a kind Dead Vlei.  There are lots of Oryx to see.  From there, you can visit the famous Skeleton Coast.  There are huge sand dunes there as well that go right down to the ocean.  We took a 4×4 tour that you can read more about here.  There is also the resort town of Swakopmund.  If you want something more exclusive there are some world-class private resorts in the surrounding deserts.  Also nearby is Spitzkoppe.  It’s really just a giant mountain in the middle of nowhere.  The mountain is really cool though.  It’s a fun area to explore and one of the best campsites ever.

Ok, now to the highlight of the trip… the safari.  Unlike most countries, you can tour Namibian parks on your own.  The most popular one to visit is Etosha National Park in the north.  We spent 4 days in the park and saw every animal we had hoped for.  The highlights are Chetahs, Leopards, Rhinos (white and black), and Elephants.   We went in late May and had many of the areas all to ourselves.  The park has some nice places to stay inside of it and each one has its own fenced waterhole where you can watch animals more leisurely and even at night lit by red lights.

Incredible Mountains – Patagonia (Chile & Argentina)

When:  November – March

Length: 1.5 Weeks+ 

I think the is these are the best mountains in the world.  The whole area feels very unexplored and wild.  I flew to the tip of South America at Punta Arenas, Chile.  You could also fly into El Calafate, Argentina but it is more expensive.  There is a good bus network to take you from area to area.  Most of the busses are 2 levels and in good condition.  The seats are comfortable and you get great views of the landscape.  The accommodations are generally very cheap but there are high-end options.

There are several highlights.  The most well-known place is probably Torres del Paine National Park.  Here, I spent 5-days backpacking “The W”.  There are less demanding options though.  It’s possible to do a long day hike to the base of Las Torres.  Also, there are Refugios along the route.  These are basic hotels that offer room and board.  In fact, it’s possible to hike the full W only carrying a day pack.  Another low effort activity is to take the ferry across the lake and spend the day on the other side or take another boat to a glacier.  Even if you just rent a car and drive around the park, you’ll still have plenty to see for a couple of days.

To the north, El Chalten is perhaps the best mountain town in the world.  It sits within Los Glaciares National Park and at the base of Fitz Roy (the mountain in the Patagonia logo).  Along with Cerro Torro, these are 2 of the most distinctive mountains anywhere.  From the town, there numerous day hikes to see all of these sights.  Most are moderate in length and difficulty.

There are a couple more highlights to round things out.  Outside of El Calafate is the enormous glacier Perito Moreno.  You can simply observe it, do a glacier walk, a glacier climb or several other activities.  To the SE of Punta Arena, it’s possible to see a couple of varieties of penguins.  I took a ferry over to the island of Tierra del Fuego and saw Emperor Penguins.  This is also about as far south as you can go outside of Antartica.

The Safe Pick – New Zealand

When:  December – March

 Length:  2 Weeks

I don’t think New Zealand is overrated but it is much more mainstream.  The culture isn’t all that remarkable or different from the USA.  However, that may make it a better fit for you.  If you don’t like to get too far outside of your comfort zone, you’ll enjoy it.  For this trip we, again, rented a car and made it a roadtrip.  I’d focus on either the North or South Island exclusively.  We only visited the south.  This is the most expensive option yet.  Prices in New Zealand aren’t terrible but they are similar to the USA.  My camping a lot, we kept the cost down.  You can see the full breakdown here.  We also spent 2 days in Australia but I don’t feel that was enough to give any real opinions of it.

You’ll arrive in Christchurch.  From there, I’d head to Lake Tekapo before continuing to Mount Cook National Park.  This is one of the highlights of the island.  If you’re up for it, hike ALL the stairs to Sealy Tarns.  Continue south to Wanaka.  I think you’d enjoy spending some time there.  Queenstown gets all the attention but it’s not nearly as appealing.  The most well-known place to visit is Milford Sound.  Fortunately, it’s not overrated.  If you have time, it’d be nice to spend 2 days there.  Overall, the country is very accessible.  There are plenty of excursion type activities that require no planning.

Bonus Options

Thailand

I probably should have done a full write up on it.  Honestly, I’m tired of writing.  January is an ideal time to visit and there is a large variety of great things to do.  It’s fairly cheap to get there and extremely cheap once you do.  We went there on our Honeymoon along with Cambodia (Ankor Wat) and Malaysia.  You could also tack on Singapore.  Look at my Facebook albums “Civil Unrest at It’s Finest” and “Third World Bliss”.  There’s a little bit of everything… mountains, beaches, big cities.  I can give you more info if you like what you see.

Madeira (Portugal)

We’re really big on this island and talked about it at length to you.  Unfortunately, January wasn’t the best time to visit.  You still could but it would be a little cool (highs around 60).  If you don’t mind cool (not cold) weather, you could look into it.  You wouldn’t be able to swim but you could do most of the other things.  It would be possible to visit in just a week but I’d shoot for a week and a half.  See my album “Island Dreams”.

Costa Rica

I know you’ve been but this is a good option for January.