I actually never complete my sim's aspirations. I'm more focused on building friendships and having a family. But sometimes I try to complete one like the painting aspiration, because you just need to make paintings and stuff. I think when your sim has a creative hobby, it's more easy to complete that aspiration. And if I take a look at the Successful Lineage aspiration, isn't that impossible to complete? Your (grand)child needs to reach the top of a career. But I think your sim will have died of old age by then.