I prefer using a monospace font for chat text. It's what I have set up for Konversation, Thunderbird, and Quaternion. However, I don't see any such option in NeoChat, where it uses some default variable-width font. Additionally, the font size in the chat window is rather small, making it uncomfortable to read, with no option to change it (the font and font size for the Room information and Members list is fine to me, though).

Konversation allows setting custom fonts and font sizes for different areas of the chat window, and having similar options in NeoChat would make it much nicer to use.