Getting a theme to match your MyBB, just knowing how to change your index to Home.php. It's pretty evident you know what you're doing, not to mention it looks great!
I'd change the the banner at the top or do some photoshoping adjusting the color and making it a bit sharper. as well as some of your other images and perhaps larger font size, used to be about the small text, leaning more in the direction of larger lately.
Also idk, try to combine some of the navigation with some dhtml scripts so there isnt so much navigation on the side apparent. Right now its sorta confusing with so many options.
Could you provide a few examples of those images? I haven't seen any that aren't clear.
As for the small text, that sized font is the only font size compatible that won't screw out the layout. If you dig deeper within the site, you'll see larger font sizes.