Eriaz(kind of)

Use interesting character names

Why name your character Sarah when you could name her something more complex and memorable like Lexington or Hazel? Basic run-of-the-mill names come across as boring and are likely to make your character more bland as a result. There’s a reason that people remember Katniss and Peeta over Sophie and Josh. Also, you can add name symbolism to enrich your themes and characters. In Siddhartha, the main character shares a first name with the famous Buddha and the themes of philosophy and religion are that much more complex. (Plus it’s a cool Easter egg)

Use Symbols and Motifs (that are relevant to the plot/theme)

These can be anything, from religious symbols to ancient civilization motifs, heck even death. In Croak, the main plot is centered around the idea of death and the afterlife so symbols like black hoods, scythes, and even death puns are littered throughout the series. In Kill la Kill (manga not book but whatever), scissors, thread, and clothes are used to relate to the plot of sailor uniforms and fashion (as well as deep symbols to the themes). You want to give your book a vibe instead of a hodgepodge of different ideas and themes stacked on top of one and other. Be focused and direct with your setting and symbols.

Strike a balance between introspection, dialogue, and description

The worst thing, personally, for reading old classic novels is that there is so little dialogue and character interaction. Almost everything is description or character introspection which can be a drag to get through. On the other hand however, barely anyone wants to read straight scripts with only dialogue. There needs to be a healthy balance between the three to get a good feel for the characters, the setting, and the relationships and bonds.

Don’t be so blatant with your themes

Nothing’s worse than having a character bring up deep philosophical conversation in the middle of a casual conversation. Your theme, if you include one, should integrate seamlessly into your story and should really be shown rather than told. Miss Kobayashi’s Dragon Maid is an anime that accomplishes sliding philosophical thought into conversation to great effect while still feeling natural. There also shouldn’t be a huge time stopping conversation spilling all your themes out at once. Take it slow and make it meaningful, not some gaudy piece of crap.