If you’re not interested in animals (horses, sheep, goats) then you may not find so much to do in Horse Ranch. The world is beautiful, the BB and CAS are nice, there is nectar making, but I think it’s mainly the animals that make this pack so good.
On the other hand, I personally wasn’t that interested in the whole tenants/landlords thing, but I still find plenty to love in For Rent. As well as the beautiful world (which you can use boats in if you have IL), BB and CAS there are the new kitchen appliances, new maintenance objects, functional radiators, lot challenges, mould, hopscotch, marbles, new cultural aspects, and probably a load more things I’m forgetting.
I personally am an animal lover so I would always go for animals first, but if you’re not, you may really enjoy For Rent.