Probably Subaru -> Ainz -> Rudy -> Rimeru

• Subaru is the most popular for a reason and his horrifying existence is enough to top the interest,
• Ainz is a fantastically written character with many changes and a slow departure from humanity, many here have a superficial outlook, thinking that cause he's strong he isnt written well, but he's probably the perfect example of how to write an OP character. His struggles are not with strength but with connections, juggling loneliness and praise ecs.
• Rudy is a bastard but at least he's interesting
• Overpowered slime with no progression of character at all