-off staff mode, on player mode- I'd think this is a good feedback, given how such little details may potentially spice up the forum abit, just that we don't really realised it.
Just throwing it out there as devil advocate, the more icons there are, the more... cluttered it is. Might be difficult for people to know which people talking are staff, as it stands theres regulars, donators and staff (looking at new players!) A few probably wont hurt, but I could see this snowballing into a mess if not done carefully.
I would love to be able to donate for a custom title. Since the meso already tells everyone you're a donator (which I don't consider to be necessary information, anyway)...
To make it more friendly to new people who are unfamiliar with the staff, you could potentially just allow staff 2 icons. Staff position icon first, and a flair of their choice at either the end of their forum nickname, or immediately after their staff position icon.