One great 'Oliver Queen and Felicity Smoak Fanfiction' is 'The New Beginning'. It focuses on their post - show life where they start a family and face new threats together. It's really heartwarming to see how their relationship has evolved.
One popular trope is 'Enemies to Lovers' in a way. At the start, Oliver was all broody and Felicity was this bright, bubbly hacker. Their personalities seemed so different, but as they worked together, they fell in love. Another common trope is 'Injury Recovery'. There are many fanfics where Oliver gets hurt and Felicity takes care of him, which deepens their relationship.
Thea could also be a great godmother. She's Oliver's sister and has grown a lot. She could be there to spoil the baby and also teach it some important lessons about family and loyalty.
Another plot could revolve around the challenges of raising a baby in their dangerous world. They have to constantly protect the baby from their enemies. Maybe there are villains who try to kidnap the baby to get to Oliver or Felicity. So they have to set up a super - secure hideout and enlist the help of their friends like Diggle.
Felicity Smoak is a character created specifically for the TV series and doesn't have a presence in the comics. The show introduced her as a unique element to the story.
Well, the status of Felicity Smoak's life or death in comics isn't straightforward. Sometimes she's alive, and in certain story arcs, she might be shown as dead. It all comes down to the creative decisions of the comic writers and the direction of the particular story.