Argentina itinerary dilemma (Iguazu)

Hi all. My girlfriend and I are travelling to Argentina this April and are planning to spend three weeks in the country. We start of in Mendoza before we head to Buenos Aires to meet up with a few friends.

From there we're planning til head to Iguazu Falls but we're beginning to second-question this plan. The reason being that afterwards we'll be heading to Salta, and it seems like a cumbersome journey from Puerto de Iguazu to Salta. I know everyone says that Iguazu is soooo amazing, but is it really worth it travelling that large distance to see some waterfalls? What is your experience?

Secondly, if we're going we plan on spending 1,5 days there. Arriving in the morning on day 1, where we'll see the argentinian side before sleeping somewhere in Puerto de Iguazu. On day 2 we'd visit the brazilian side before catching a flight from the argentinian side at 3pm going to Salta through Buenos Aires. Is that a realistic plan?

And does anyone have some kind of magic tip to travel to Salta from Iguazu that I haven't realized?

Thanks in beforehand!