Few comments over excellent suggestions above:
We were at Quilotoa two weeks ago. The trail from Q to Chugchilan was washed out so locals did not recommend walking there even with a guide (I did same hike last year) and the dirt road for cars also looked very bad. So condition may not be ideal to travel to Chugchilan. Otherwise, I really like the area. In Chugchilan, I prefer Mama Hilda, excellent and friendly place at the fraction of the coast of Black Sheep, which tag I simply cannot stomach. In Q. itself, hikes along an down the rim are great as well as a boat ride over the lake. Accommodations and food are cheap, if basic.
Termas de Papallacta is a great place to relax but expensive to most backpackers. But we could manage by going there with whole family and renting a family cabin (2 floors, sleeps up to 6) and you get semi-private pools. There are less expensive places there, of course. It is often misty or rainy but you still can enjoy great hikes and guided at Explora-something outfit are knowledgeable and inexpensive.
Laguna Cuicocha. There is a cheap hotel with a restaurant, I believe it is called Mirrador, but I may be mistaken. It was listed in my old Rough Guide (I just checked e-version of LP and it does not have it.) When we stayed there in 2010, they had rooms in the building where restaurant was: it had heat but not ht water or rooms in a 1-story barn-type wodden structure with hot water and stoves (but make sure to get plenty of wood before they are gone for the night.) We loved the experience, the sunset was majestic, though it got very cold at night.
Enjoy your travel!
/alter
