My tuppence worth: AAM is easily one of the best Irish sites on the Internet as it offers endless advice on important financial issues. That's its primary focus and it excels at it, but some of the non-financial sections are also beneficial (e.g. Home & Gardens give people excellent help on all things related to their primary investment - their house, and the advice gained on their empowers a lot of people when dealing with the trade, and also helps people to fix problems themselves, all of which saves them money).
Fair play to Brendan and all the mods for all the trojan work they do in running the site, and I for one would have no problem with seeing a banner advertisement at the top of the site in order to cover costs and give the mods a reward every now and then, though obviously this would be from a financial institution which would raise issues on partiality etc.
As I've said in the past, taking a narrow view that this site is only about money and anything else isn't really welcome will be detrimental to the long term success of the site. Sure, you could say 'if you want to talk about that go to boards.ie', but some people will go there, like it, and never come back, thereby depriving this community of a potential contributor.
That said, you cant have people coming on here just to waffle in meaningless threads (I would categorise any thread that doesn't 'help anybody as meaningless. e.g. knowing how you like your Creme Egg doesn't help anyone, but pointing out a great deal you got, or how to fix your PC does help people).
So, in short, my solution would be to lump all categories that don't help people into one section (i.e. add more to The Depths), and clearly advertise that this section will only be moderated to prevent against libel - i.e. there will be no quality control. Once everyone knows what to expect in there, and it can be skimmed to prevent libel, anyone using it couldn't complain about standards, though many would be happy to use it regardless.
Oh, and I do agree that the number of people posting threads without searching for previous ones on the same subject is growing and is frustrating (e.g. how many 'About to build extension, what is the cost per sq ft?' threads have there been recently?).