We stayed 2 nights at the iguazu lodge in a family suite. The lodge had 2 bedrooms and a living area. The terrace was just a couple of balconies unfortunately, though other rooms did have large terraces per photos you will see. Bathroom wasn't great, awkward shower, nothing special.
The staff made the resort being welcoming, speaking many languages and arranging all you could need. Restaurant on site had good food at breakfast and the dinner we had one evening was lovely at a good price. The pool wasnt available to comment on, but looked to be a winning feature in the summer months.
This lodge is on the edge of town, about a 10-15 minute walk on a partially rocky road. This means it is nice and quiet, but bars and restaurants in downtown are just a bit too distant. For me I would book a cheaper hotel in the centre next time as I do enjoy a few beers :-D. On a wider scale any location is fine with a few km walk to the 3 country view and a short drive to the falls/brazil (border can take 45 mins). An advantage of staying in Foz on the Brazilian side is that popping to Paraguay is easier which may be a consideration. More