Hi, thank you for your suggestions again! I am glad that you take the time to think about the features of debato.
the features you mention indeed came to my mind as well, but besides the upload features, I had reasons for not including them (yet).

The core concept of debato is to get rid of the cluttering of regular comment sections and put the many sub-discussions in the debate structure. If it would be possible to reply on comments directly there is the risk of a discussion evolving in the comment section rather than as arguments. By tagging however, it is possible to provide simple responses to comments.

Also a list of upvoters was not included to keep the focus on the arguments rather than the people spending voting power or who supports a certain argument. On the other hand does this feature might result into a more personal experience when debating arguments.

Feel free to comment on these ways of thinking. I'll definitely keep them in mind.