I like this idea... I would structure it as follows:
Basic level membership: No perks, as is now..
Donation level membership: Users can choose how much they want to donate to the site and for this they get something along the lines of "PSC Sponsor" under their username, can view How to guides and can edit posts.
Full paying members: These members have full access to all areas of the forum, have avatars and signatures AND get a discount from shows etc subsidised by the club as per previous ideas in previous posts.
Obviously the Full paying members can be split into web only and membership pack prices as they are now if that idea was to be kept on...
Just my 2 cents...