Comment versus UserComments

I wanted to raise an issue about how to represent comments (e.g. on blog
posts).

There are many subtypes of CreativeWork, but Comment is not one of them.
Perhaps it should be?

Instead, it seems like comments are to be represented by UserComments,
which is a subtype of UserInteractions. But apart from UserComments those
types appear to be for aggregates, not for an individual
comment/tweet/like/etc. The type names are plural and don't really fit for
non-aggregates.

I think the aggregate types are useful, but for each aggregate type I'd
like to have a clearly defined type for the individual thing. What's the
right way to achieve that?

daniel