Id love to know myself maybe try http://seoforums.org/ they have a multilingual forum and you are more likely to get Korean SEOs there with some experience

1 there is no point having canonical on a 404 page. I would say its a very confusing signal to bots

2 don't always 301. 404 exists for a reason. In most cases I will 301 old pages but there are cases where letting pages 404 is the correct way forward

It is not that having H1 and Title the same is damaging, it is the overall quality and trust metrics of many websites that employ this methodology that is the cause of problems: simply, correlation vs causation

In EGOLs case its fine as the rest of the site is fine, in other cases it may seem bad, but thats just because the rest of the site is bad

Best if you give the urls but I would say its a "Good Thing TM" .

A rich page of content around a keyword topic with mulitple media types is the way im building my content now - even if it doesnt work for Search Engines, its nice for people (crazy, huh?)

I print it out and lay it out on a large table in the office. Just seeing it visually lets me get to grips with it a lot easier than scrolling through unconnected pages on a screen.

Print small and get a big table and you can fit a large sitemap there Get a lot of A4s and some scissors and tape and you will be surprised how much better your understanding is by the time you've finished