G.I. Joey - not breedable
Mamaroo - Earth and Fire, 16 hours, can be bought for a steal at 50 gems
Mama Bear - Dark and Water, 13 hours, 120 gems is not a bad price
Puppy Love - not breedable
Papa Penguin - Water and Earth, 14 hours, 110 gems is a good price, but I believe he was recenty a Spin to Win animal, so you might have got one that way
Electricutie - Lightning and Water, 23 hours, was available on Spin to Win a while back
Grandmother - not breedable, not on a recent spin to win, 100 gems is a good price
Unicorgi - not breedable, 200 gems
Hot Dog - always available - not sure why they put these animals on sale
Fluffy - not breedable
Lambi - always available - not sure why they put these animals on sale, 80 gems isn't bad though
Swan Princess - not breedable, 160 gems
Swan Prince - not breedable, and not very affordable at 480 gems
Melodeer - The only way to breed this fellow is by breeding a Lullabison with a Tubacan. Doesn't look like this option is currently available, so you can get it for 120 gems, which isn't bad
Island Amakihi -not breedable
Dragon Roll - not breedable, current spin to win prize and one of my favorite critters - I like puns, and I like the animals that roll
Jungle Dragon - not breedable, current grand prize in the leaderboard
Sear Khan - not breedable, final prize for completing all milestones in the current leaderboard

NOTE: Mamaroo, Mama Bear, and Papa Penguin are pretty cool because they start out with no babies, and as you grow them and evolve them, they get their babies. Mama Bear ends up with multiple babies, I believe.

Habitats:
Jungle Nook is so ugly - I regret buying it for my old accounts. But it holds 5 animals.
The rest of the sale habitats this week only hold 4 animals each, but the Fountains of Youth are a lot of fun to have.
Animal House is the real steal this sale because it holds 5 animals and is on sale for 250 gems. However, it only holds Earth and Nature animals, so it is limited in its utility.