two weeks gives you time to visit some corners of the country, if you can afford plane cost much better.

i would first stay 2 nights in iguazu. go by plane, return by bus and stop at the wetlands for l night (it is halfway to buenos aires).

I would never ever miss Salta and Jujuy both ways by plane. 3 nights in Salta l night at the humahuaca heights. Not to be missed.

If i had to choose among the Bariloche, Mendoza, Cordoba and Ushuaia. i would go to the last one having then the possiblity to share my stay in the glaciers. 2 days in Ush and 2 days in the glaciers.

This would give you time to stay in the city of Buenos Aires. Hotels are quite affordable and you can find well located ones for 55/60/70 dollars the night both with good breakfast. is it worth to pay more if the place is good, comfortable and in a good area????. Bed and breakfast are cozy places to stay and the hosts are very friendly towards tourists.

I would definitely save money on accommodation, buenos aires offers good places with good service so take them. Visit all argentina with the difference, you will not regret it.
Plane tickets are expensive just because the distances are long. But you avoid wasting time and energy that is why it is worth the money.

Restaurants are always good because our meals are based on the best meat. that is the difference. You can find exc places in Puerto Madero, Recoleta and
Palermo. Many people know a lot about good restaurants and they can give you better advice.

Lots of luck