Right, speaking here as a mod and as co-head of Remus' Reflections now. (But still only posting my personal opinion here, not that of any collective.)
I'm not sure I actually get your problem.
Do you think there aren't enough places to get your post count up in to fulfil the requirements for joining SPEW and the SBBC? I've never been in either of those clubs, and I don't even post as much as others do, yet my post count would qualify me to join ten times. Admittedly, I've been a member for a while now, but I still have an average of 1.13 posts per day - and that's with a lot of lurking in the busy RL times at some points. If you manage to do two posts per day (more to that in a second), you can apply to the SBBC within a month. And I don't think you even should apply there right after joining the boards, because it's always better to get familiar with the whole environment etc. before making such a commitment.
Now, about the posts per day: I'm NOT telling you to spam just anywhere (please don't do that, haha), but you have so many places on MNFF here where you can post! You have the Character Clinic with three subforums - and there's always an OC that could use your help - there's always an open question in the Reference Desk... You can comment on people's work in the Excerpts of Murtlap forum.
Then you can set up a drabble thread and comment on others', you can set up a drawing thread and comment on others'. You can participate in the "General Fanfiction Discussion" subforum to get to know people. [Even if not all of them increase your word count (I'm not sure which do now, I thought they all did, but your post implied differently) they are great places to get in touch with people. Also, if getting to know others - for potential recommendations, for example - is your problem, get out there and PM someone you think you might like to get to know better, or contact them via AIM. No one will bite you for that.] You can participate in the RR discussion....
That actually brings me to my next point.
Could you clarify what you mean by the part that I bolded? There are two parts of RR - one is the drabbles, and the other is the discussion. You can participate in the discussion as much as you like. What do you mean by "drabbles that are chosen by mods"? Obviously, someone has to pick a winner. The "Best Reflector" is something that's decided by a poll. Did you mean that we choose the topics? Well, someone has to, and trust me, we put a lot of thought into this and try to pick topics that seem to be popular around the boards at the time. And then, every now and then there's a challenge for members to submit topics... And, as with all parts of MNFF, we're always open to suggestions.
I've seen Remus' Reflections and it looks interesting. It's not the sort of thing that's available on other message boards. I just wonder whether it has to be limited to drabbles - and only drabbles that are chosen by mods. Mods do give the most time to the improvement of the site and I'm not suggesting that they contribute less. I truly believe that people will be more active if you give them an opportunity to issue challenges in addition to mods. The type of things that I'm suggesting are complementary to the system that is already in place, it's not meant to change it.
So what exactly is your suggestion on improvements? It's really not that anyone is opposed to change or anything, I'm just not sure I'm following you. Do you want members to ask more questions? You do know that old threads (where no further help is required) are locked and graved, right?
What I'm asking is that you have a look at the Hospital Wing quickly. In the plot section, there's only one page to the forum - one - and half of them are sticky posts and rules. I appreciate the need for the system. I just think that the system can still be in place whilst making some improvements. It's impossible to give that many thoughtful, meaningful answers when there are so few people asking questions, is all that I mean to highlight in this post.
Again, I don't entirely understand your problem. We HAVE threads for individual characters. If you think there's a character missing, you can always add the thread in the appropriate subforum. The main aim of those threads is to ask questions, of course, but if you want to post your opinion on something and leave it for discussion, as long as it is on topic, I don't see the harm in that. Most people just ask questions about what interests them at the time or what is relevant for their stories - which is the main purpose of those threads.
For instance, in the Character section, there could be threads for Hermione, Prof. Bins, etc, etc. You could also add threads for character pairings. Posters can then give character sketches, essays, analysis, the pros and cons for the particular pairing, etc.
If you look at Hogwarts right now, you'll see that we do have workshops. Currently, the one offered is on drawing. I think you mean tutorials that remain on the site as one post, with no student/teacher thing, but more like a single lecture, yeah?
Instead of just classes, once-off tutorials could be added on various aspects of writing and the HP Universe.
I actually doubt that would make sense. People are much more sure to read (and actually find) things when they're enrolled in a class or workshop. And it's much easier to learn and remember when you get the professor's feedback on the work you do. And then what would you include in those tutorials to make them not unreadably long, but still useful?
Maybe you should have another (closer) look at all the forums and subforums. I feel like a number of the things you suggested are things we already have/do around here.
I'm sorry, I'm probably misunderstanding most of what you said... I'm sure you have a couple of great ideas though, so maybe you could clarify what exactly you are suggesting.