What problem does this address?

The Latest Comments block has an option to show the comment excerpt.

Having an option to show the entire comment would increase the block's flexibility.

What is your proposed solution?

Replace the "Display excerpt" toggle with a "Display content" dropdown with these options:

• No content
• Excerpt
• Full content

On the PHP side, it should be enough to call get_comment_text() instead of get_comment_excerpt() when the "Full content" option is selected.