That sounds a lot better than your original description!
If you are going at the right time for whales, then Peninsula Valdes is pretty amazing. I remember asking, when booking a boat trip there, how likely I was to see a whale. I expected the usual waffle about how viewings can't be guaranteed. Instead, I got a really puzzled look from the man and the statement "You will see whales". During the trip I realised how ludicrous my question was - they were everywhere.
Some people rave about BA, but I found they were typically kids who enjoyed partying until dawn. It definitely wasn't my favourite S. American city, but if it is your first, then I am sure you will be entertained for a couple of days. Not sure if things have changed, but pay attention to warnings about street crime.
Fairly sure I didn't cross the steppe there, but if the purpose is to see Llamas, Alpacas, Vicuña and the other one, as well as take in the scenery then it is worth doing.
I'll see if I can remind myself about the other places in a few days. I'm away at the moment.