Argentina is amazing in terms of landscapes, culture, night life, whatever. However, if you like the kind of "archeological" tourism, you might get disappointed, there's hardly nothing before Spaniards.
Buenos Aires is usually known as the "Paris of the Americas", but in fact it looks more like Barcelona. Either way, it's a ride, and way more exciting that those boring frenchies
If you like breath taking landscapes, anything close to the Andes, whether in the North or in Patagonia is incredible. And of course there are lot of activities. Patagonia and Cuyo zones are more for regular mainstream tourism, while North (Puna) is for those looking for the real South American experience. Plus, you can cross to Bolivia and even reach Machu Pichu in a 3 days journey (counting back and forth to North of Argentina and 1 and a half day in Machu Pichu)
If you want EVERYTHING (landscapes, night life, tradition, modernism, culture, food, etc) you need to go to Cordoba. It's the second city in Argentina, the most beautiful, the most historic yet the most modern and it's 30 minutes from tens of touristic destinations.
If you like beaches, Argentina has big beaches, but nothing "tropical style" and water isn't very clear unless you're in Patagonia (which is COOOOLD!!!). But if you go to Patagonia, you may go to Antarctica. And then... you'll be seen like someone who went to the moon, there are no words to describe it
All of the above are just a few reasons why, being able to live in Europe or US (I'm Italian and my first son is born and lives in USA) I'd never move away from Argentina if I can avoid it.
And let's not even start with food and women
: in Argentina steaks of the finest meat in the world are EVERY DAY meals and we get bored of them. As for women, they look more European than Latinas, but the breed is impressive, a girl looking like Jeniffer Lopez is pretty standard here.
Yes, I really love MY country!
PS: the downside is it isn't very cheap. Going to Peru, Bolivia, Colombia, Venezuela and even parts of Brazil may cost you half or even less money