Just finished Northanger Abbey – what should I read next?

I finished Northanger Abbey today and really liked it. I tend to like Jane Austen's work usually. Before that I read The House in the Cerulean Sea and loved its vibe. Some things about me –

1. I hate sad endings.
2. I like mysteries which are fast paced – like Agatha Christie's Poirot series and The Thursday Murder Club (bonus points if it is funny as well)
3. I haven't read sci-fi or dystopian world books in a long time but if there is something easy to read, I am up for it. I read Hunger Games as a teen and really enjoyed it.
4. I am restarting reading regularly again at the age of 24, simply because I like it and I want to make time for the things I like and make me happy.

Help a girl out please!