Let me explain.
Ragna is a limited character. He has good neutral, average pressure, and average mix-up. He doesn't not have many tricks readily available to his arsenal. He does not have any single strength or area in which he excels.
This forces you to outplay your opponent with the little tools he provides you in comparison to the rest of the cast. It forces you to mess with your opponent harder, surprise them more, while still having to maintain a very solid play style in order to stay alive (10k health is "fun", I'm sure you all know that). It provides a really fun challenge. There's a reason Ragna is one of the hardest characters to play at high level, and why many hold the opinion that he's in actuality a weak character. Everyone else has several options, several tricks to pull out (unblockable resets, safe cross-up shenanigans, many revolver action options, strong primer breaking strings, really strong oki for example) and most every character has an area of strength. In comparison to him, they have a huge arsenal.
But to me, I don't like having more options than I know what to do with. I like having very little, and making the most of it. Simplicity. Give me the basics, let me work magic with it. That's just how I like things.
Don't know if that made any sense, but that's just how I see things. I do love messing around with other characters though, but only for their combos~