Well, a frequent theme is the impact Spike had on the lives of the other ponies. In a funeral fanfic, the ponies would probably come together to celebrate his life. There could also be a theme of acceptance, as the characters have to come to terms with Spike's death. It might show how they grow from this difficult experience and how their relationships with each other change as a result.
In Spike MLP funeral fanfics, a common theme is the sense of community. Since MLP is all about friendship, when Spike passes away, the community of ponies would gather to pay their respects. This could involve them sharing stories about Spike, which not only helps them deal with their grief but also shows how Spike was an important part of their community. There could also be a theme of legacy, with the ponies thinking about how Spike's actions and presence will continue to affect them even after he's gone.
One common theme could be grief. The other characters in the MLP world would likely be mourning Spike's loss. Another theme might be reminiscing about the good times they had with Spike. For example, Twilight might remember all the times Spike helped her with her studies or magical tasks.
One common theme is friendship. Since Spike and Luna are from different parts of Equestrian society, their friendship can be explored in many ways. For example, how they bridge the gap between a young dragon and a princess of the night.
A common theme is friendship. Spike often forms strong friendships in these fanfics. He may befriend other animals or ponies and they go through things together.
Friendship is a very common theme. Since Applejack and Spike are from different species in the MLP world, their friendship is often explored. How they support each other, understand each other's differences and grow closer.
Friendship is a very common theme. Since Spike and Fluttershy are both beloved characters in MLP, many fanfics focus on how their friendship develops. For example, they might help each other overcome their fears or insecurities.
I'm not sure specifically which Spike MLP funeral fanfics are out there. You could try searching on popular fanfic platforms like Fanfiction.net or Archive of Our Own. They usually have a wide variety of My Little Pony - related fanfics, and you might be able to find some related to Spike's funeral.
In many MLP Spike high school fanfics, the theme of acceptance is prominent. Since Spike is a dragon in a pony - centric world, he has to deal with being different. Also, the theme of academic achievement and the challenges associated with it are often explored. Spike might struggle with certain subjects but also strive to do well. There are also themes related to extracurricular activities and how they shape his character.
Adventure is also quite common. Since the My Little Pony world is full of magic and different lands, fanfics could have Sweetie Belle and Spike going on all sorts of adventures. Maybe they are searching for a lost magical artifact or trying to rescue a friend from a dangerous place.
One common theme is friendship. Since they are from different species, their friendship development is often a central focus. For example, they might start off as strangers but gradually become close friends through shared experiences.
One common theme is friendship evolving into something more. Spike and the reader often start as friends and then develop deeper feelings. Another theme is self - discovery. As the relationship progresses, both characters learn more about themselves.
One common theme is friendship. Spike often gets involved in stories where he helps the Equestria Girls strengthen their friendships or overcomes challenges together. Another theme could be adventure. He might go on exciting adventures with the girls in the human world or the Equestrian world.