I'm not entirely sure which specific 'all hallo games' you are referring to. There could be many indie or niche games with that name. Maybe it's a local or very specialized gaming project. Without more context, it's difficult to tell the exact story.
One of the best elements is the expansion of characters. Fanfics can give more depth to characters like Garrus, showing his life outside of Shepard's missions. Another element is exploring new planets and species. Some fanfics create whole new ecosystems and civilizations. Also, the ability to rewrite certain plot points in a more interesting or satisfying way, for example, giving a different ending to the Krogan Genophage storyline.
As I don't know the specific 'all hallo games' story, I can't say for sure. But if it's a story - based game, it might have characters with unique personalities as a main feature.
Sure! One great 'Mass Effect' fanfic is 'The Shepard Chronicles'. It delves deeper into Shepard's backstory before joining the Alliance. Another is 'Mass Effect: Redemption of the Rachni' which offers an interesting take on the Rachni species. And 'Liara's Journal' gives a more personal view of the events through Liara's perspective.
Black and white cartoon fuesalage often has a classic and timeless look. It might focus on strong contrasts and simple yet effective visual storytelling.
You might try looking on some popular comic platforms or websites. Sometimes, specific comic forums or communities dedicated to this type of content could have it.