The Brazil side HI hostel worked well for me: food, drink, conversation, pool, football pitch, hummingbird feeders....The parking was not exactly fully secure, but I asked and was granted permission to pull my bike around through the camping area and stashed it fairly well. Didn't seem to be any significant crime out there.
The hostel I looked at on the Argentine side made the very luxurious Brazilian one look austere.
I surprised myself by enjoying the dam tour and the bird sanctuary. There are also small waterfalls to walk to, ponds to swim in, and hangovers to nurse.
Hope you're having fun, Mike. Working for a living's not all it's cracked up to be.