Suggestions are always welcome, so I'll address a few of yours.
Personally I hate this. Sometimes you need to check fansubbers'/scanlators' forums for random info and I absolutely abhor the requirement to register to see anything but the forum rules stating you need to register to see anything but the forum rules. So, to follow the ancient axiom, I'd rather not subject others to something I don't like being subjected to myself.
Blogs were a new feature brought by the recent engine upgrade. Thus there was no tradition with blogs. We are hardly living our heydays anymore, so it unfortunately makes sense there aren't much going on there. Still, I don't think they especially distract from anything. Kind of like an extra feature in your car you never use but that's impact on the price was so insignificant there was no reason to get another model because of it.
Forgetting the fact it would break Marik's heart, that would actually be quite cool. However, I don't know who would/could code one. It would take some programming after all, plus it would need someone to fix a list every season (and update it a few times during a season) to match the release with the thread. And to select which releases are worthy to post in the thread. Finding such a somebody is always a tough job.
I can't say that much about this. I have never used the feature anywhere. The only time I'd have liked to, was at the Megatokyo webcomic forum where I'd have liked to ignore one fucking annoying and idiotic moderator that never had anything remotely intelligent to say and only pestered everybody. But the lousy forum engine didn't have an ignore function despite being commercial. Fortunately he got kicked out eventually. Seriously, the dude was more obnoxious than krb. So, I think anybody gross enough to really be worth ignoring should be bannable already.
The real use for the ignore function, thus, is by immature, emo people, who lost an argument and afterwards think it's cool to ignore the winner. However, there's no legit reason for us to discriminate against immature people as long as they behave otherwise. So, it's their own choice.
There's already the minimum length requirement you mentioned. Otherwise moderators are supposed to delete useless posts as those are forbidden by the rules. I personally think this work well enough.
Seems like the General Support is that technological forum since there's little of anything else going on there. It's anybody's question why that megathread (and the "PC Problem..." as well) accumulated nearly all computer build related stuff and questions, but that's just how it happened. There's really no reason to keep doing it. You see a few separate threads every now and then.
The somber fact is that Gotwoot isn't active enough to divide discussion into many subforums and still try to look like active. You sometimes see new forums out there that have 50 categories each having one or two posts. That's more sad than neat.
Absolutely not! Request denied!
What on Earth, man?! Erase all of our history? That would make us look like nothing but a wannabe new forum with a limited bunch of members (some of which would leave to boot after such a deed) and hardly any posts even after another year. Either brilliant or terrible, all the threads and posts and posters are a part of the glorious Gotwoot history. The most dreadful time of Gotwoot history actually was when the infamous krb suddenly decided to eradicate one of the more popular members and ended up deleting all his numerous threads as well, thus wiping a significant part of Gotwoot history away. A forum is its members and the members' posting history, nothing more. To remove that history is to kill half of what a forum is. Even bad history is still history.
They are always welcome, even if it looked like I did nothing but use my time to shoot them down.