@Rambling_Rose314What I usually do anyway is to create a few townies of my own and keep them as future possible partners for my Sims. Sometimes I create my Sims in say, a flat share and then move them out. I move the "spare" Sims into Other Households but my Sim has their friendship with them so if I decide to start a relationship with them they have a head start. They don't even need a house, you can move them out.
I also add a few random solo Sims or pick a few NPCs in Other Households and edit everything about them, again to make them more suited to my Sims. I tend to go through Other Households regularly, culling random NPCs and editing others or adding some of my own.
So that's just an idea to make relationships a little easier for your Sims. You mention Legacy there which I don't play, so maybe the second option is better for you.
