Lowkey, I bow to your dissenting opinion.
To clarify, I have no general objection towards long posts. Nor to the voicing of strong and differing opinions. But I would prefer them to be kept factual - and I did get the impression (possibly falsely) of some personal animosity creeping in the last discussions.
ad 1) I concur, and endorse, that non-constructive criticism can be a killer - in writing reviews as much as in life. Though I cannot complain in that respect in Winterfox's comments towards me and my input. His comments were factually stating his personal opinion, which were up to me to accept or decline.
ad 2) Emotional history certainly impacts, and should. Emotional state does also, but maybe should not. That is my purely personal feeling, of course - but trying to convey a strong feeling in writing, so that others can understand (and share) it, others who, while reading it, are in a completely different state of mind, seems very hard to do. To me, that is not so much a question of not finding the energy - actually one may be full of energy at that moment - but the state of mind may make you say things, that you would not want to, or not in the way you would want to (There is a reason why there is the rule, that you should not write a complaint before having slept over at least one night)
ad 3A) A rethorical question? A failure to read - very probably not. A failure to appreciate, respectively to question oneself as to whether the author's intent was understood correctly - maybe.
As to the author's responsibility - as a reader I appreciate books where the author leaves room for my imagination, and does not describe everything in detail. However the balance must be carefully weighed as to what I (reader) need to know, and what is just nice to know in order not to have to challenge my imagination (which some may not want to). But IMO, this should not extend to weaknesses (e.g. logical flaws).
ad 3B) Correct spelling and grammar, as well as a structured text, make reading easier - especially if you are doing it in a foreign language. I would expect an author to make a honest effort - none of us is without typos.
I do not think that this would as such restrict the development of ideas - it is just a tedious effort, that has no creative touch, and usually is the hard work after the creativity.
The writing style is possibly something different, as this is very personal and close to what and how you may speak. I think, it ddepends on the purpose of your writing - if you want to address a wider audience, then sticking closer to the "norm" would be more appropriate.
(For example, in forums like this, you every now and then encounter some terrible chatter slang - that probably is common knowledge to any experienced chatter - but I fail to understand the question at times, and I am not the only one, so cannot help (though help is, what is sought)
So - no, I do not think the two ideas need to be in opposition, and yes, actually there should be both. Ideas can be developped as one pleases, and style may be whatever the author is comfortable with - but in the end I want the author to respect me as a reader, and facilitate my reading, respectively in a foreign language just make it possible. When publishing, it may be OK to let the editor do the "dirty work", but what if YOU are the publisher? You do proof read your posts, do you not? Why? Because you care for your readers? Because you do not want them to think of you as an illiterate moron? Because you have respect for your own language?
Is it better to write something awful than nothing at all? For whom? The author? - May be; For me, the reader? - No! But then who judges, whether it is awful or not? Right or wrong - it is me!