Okay, this is where my true inner cranky control freak will come out. As our forum grows... like, we had 130 new members in one day the other day, the propensity for members to distinguish themselves from the other members seems to be increasing and as a result the board becomes more and more crazy to read as they tweak font colors and stuff. Do you ever require that unless they have a reason, i.e., for emphasis, that they stick to a certain font size and color? Or do you just let them have complete freedom even if it means that you cannot read some of their posts.
For the sake of my sanity and other board members, I ask that they keep doing such things to a minimum so the community can benefit and continue to grow. People aren't going to read a post by mary thats in red and see another post in red and automatically assume its by mary so there is no need to use different colors or font type faces 98% of the time. If they want to be different tell them to try to understand your forum isn't a massive coloring book thats all about uniqueness and individuality... unless of course it really is then it might confuse them.
I think (or hope!) I've disabled colours... but I'm not too bothered about the font members use, as long as it's not comic sans(!)
I think it depends on the community, teenagers love to customise things and tend to have pretty good eyesight. I personally cant stand large fonts in pink but I suppose it is a way of showing your personality
I have that plugin which allows users to have a set posting font... I like users to post in differant fonts and colours, makes everyone look differant.
I wish MyBB had the default font add-on. So members can choose their font face, color and size. Anyway, no, I don't mind - I let them have freedom.
I've had a few members who love playing with the font colours. Didn't take long til they discovered that others didn't like it so much.