It mainly depends on your interests. If you love animals, farms or the wild West, you should go for horse ranch. If you like building and a tropical world, for rent is better. If you like to focus on romantic relationships, lovestruck is the better choice.
Personally I would go for horse ranch out of those three. The horses are a rather straightforward gameplay element but are well done. (with the exception of unicorns) The nectar making, mini sheep and goats and the world are fun. This pack goes very well with cottage living.
I only recently got for rent. I think this pack can offer a lot of gameplay but has a certain risk of lot corruption. The world is also very pretty, although the nightmarket is so empty that it feels like there is a pandemic going on. There are a few minor additions I appreciate like a kettle to build water and hopscotch.
Lovestruck seems great too, if you are into dating.