It seems there is contemplation on upgrading, so one or both of the following points may be default in the upgrade. I'm a phpBB guy myself, so I'm afraid I do not know.
Oh yeah, and about that consideration of an upgrade, wouldn't there be security upgrades within the new package to take into consideration? Just a side thought there, not one of the suggestions.
Okay, the suggestions:
Firstly, I think there should be some user control to enlarge board-wide text size. The font, if you will. I don't see any button anywhere for the sight impaired or older folks. One size larger might be enough. Some sites have two size increases.
True, not a lot of users would feel a need to be reading a larger font, but it is a nice feature for those that do need it. Kind of a courtesy. It's a requirement by law in some countries in some venues. Not this sort of site, but it shows the issue of helping out sight impaired folks on the Net is gaining ground.
The guys and gals at W3C have a rather concise page on this business of font/text size here http://www.w3.org/QA/Tips/font-size
although I don't agree that one size fits all
my university colleagues stuck in there at the top in a bold font. I say they should know better, but that's between us, yes? Anyway, what's even better on that page are the "Further Reading" links down at the bottom of the page.
The second suggestion I'd like to make a motion on is that teeny-weeny "Back to the Top" button down there. Seems like it could be better advertised as being there. Yes, I know its got an arrow shape. but text might be a bit better. Maybe just "Top" would be fine. There isn't even any hovering text to indicate what that button does.
Like a wrote above, one or both of the suggestions might already be built into an upgrade package, which would make this post pointless.