I noticed, in the red/dark theme, that some buttons are of a light blue color that clashes with the overall feeling. The Create Thead/Upload a File/Preview... buttons, when creating a new thread, the Post New Thread button in every subforums and the taigachat buttons for smileys, etc. Also, in the subforums, there's a column named "Replies" but it's not replies that are listed under it, it's the words Replies and Views for each thread, an the respective Replies and VIews numbers are listed on the right line, in the next column named "Views". It just feels a little weird.
I agree the blue one's do clash a little. It's an easy'ish fix though just requires a few bits of css changing.
I've been considering whether to change the button colour. It's not that bad, but it could be red, like the title bars. You're misreading the replies thing. It's not two columns - it's one column with two sort option buttons. Do you want to sort by replies, or views? Most people are never going to choose either, though.
It's misleading IMO, but I can live with it. I see you changed the blue to red, I like it, but it's not the same red as the one of the title bars. It's better than blue though.
The same one is confusing. Is this a title bar? Is it a button? Who knows?! Colours are back to proper classic colours now, thanks to Kev for the simplification. Looking a bit more uniform!