Before I start, I should just say that I've been following this project for quite a while and was incredibly happy to see forums put up for it. However, upon reading through just one topic I had already started to get burnt out on reading through paragraphs of text in a small, monospace font.
I've been a software and web developer for quite some time now, so I am accustomed to working with monospace fonts in a development environment (in which they work incredibly well), but using them for paragraphs of text can be incredibly disorienting due to how it spaces out words, working against the mind's method of reading words one at a time and forcing it to instead read letter by letter.
I feel like I might not be explaining this well, so I whipped up a Greasemonkey script that automatically forces a font-family style on certain elements with a Sans-Serif font to show comparisons (I'll use the first topic in the subforum as a quick and easy example):
Without Sans-Serif font
With Sans-Serif font ()
This obviously missed the date/time parts of the post, but as you can see in the title and content, the text is much cleaner and, at least in my opinion, much easier to quickly read through.
If Courier New is part of the branding for your new company I definitely understand utilizing it, but it would definitely be nice to have an alternate style with any form of Sans-Serif font to help with readability!
As a bonus, screencap of Topic List using Open Sans: