Well, reactions to RWBY Death Battle fanfiction can vary greatly. Some might be excited about the unique battles and character match - ups depicted in the fanfiction. It could bring out new perspectives on the RWBY characters' abilities and how they would fare against each other in different scenarios. For example, seeing how Ruby's speed and scythe skills compare to another character's powers can be really thrilling.
Inosuke doesn't become a Hashira in the manga. The story progresses with him having other significant experiences and achievements instead of achieving that specific position.
It's hard to give an exact number. Different story arcs and battles led to the deaths of multiple hashira. Some died heroically, while others met their fate in unexpected ways. The count changes as the manga progresses.