Well you can't have everything can you ? STH's only looking to rock up for the big games and to flog off the lesser games won't get much sympathy from the club, or me for that matter. Nor should they (and this certainly wouldn't be the case for "most" STH's anyway). Neither does anyone have the right to get tickets on the cheap.
And as all games are likely to be sold out this season, I can't see anything in your post which negates why the club shouldn't adopt this Seatwave.com system Fulham use, or something just like it.
I can't see anything to stop them using something similar either, but I have a question and a few potential pitfalls...
Question: If you buy a PSL will you be able to sell your seat even if the match isn't sold out? I'm not sure if this was discussed but I would hope the answer is yes or there could be a lot of unhappy PSL holders who aren't able to get rid of unwanted tickets. If people buy a PSL I would expect it's because they have a seat they like, in a good location - and these seats would be easily sold (as opposed to one in the south-east corner).
Pitfalls: One possible problem is that, if you don't have a PSL and you're off for a lengthy midwinter break or have to work away from home, the match(es) you want to sell may not be sold out at the time you leave. Under the old NSC method it wouldn't matter as you could sell them at any time.
Also, one way of just about guaranteeing your seat would sell was to set a lower price than the club would ask - which will not only be impossible under this method but the buyer may also have to pay a booking fee (I haven't seen anything to say this wouldn't happen with Seatwave).
I also think that 'most' STHs will try to attend the big games - so only the lesser games will be readily available (and these are less likely to sell out).
I'm not saying that these issues couldn't be overcome but it just makes the whole process much more complex than handing over a paper ticket and receiving cash. probably best to just go to all the games.