It seems to me that:
You want the maximum number of questions asked so that the forum is vibrant and thriving.
You want some regular, knowledgeable, users to answer questions.
Presumably new people with questions choose a forum based on seeing other questions answered, and the style / friendliness / whatever of the people providing answers.
I'm not sure without an import from the old system that an index of a few posts is going to give reassurance, to Newbies, that this is a busy forum. Perhaps that could be solve by having the links to Registration / "Ask a Question" on the old forum just bring people to this new one. Time will tell if the absence of a huge repository of past threads (in the new forum) continues to attract a decent number of newbie questions.
As someone who provides answers I want the best possible tools to maximise my productivity for the time I have available on here:
Ease of reply. At least the new forum remembers where in the thread I have read to, so links directly to next available post. That saves time. I've not yet explorered how the new forum remembers threads that I have participated in. Based on my experience with other "modern" forums I like:
List of threads I have participated in
Ability to add a thread to that "follow" list (without replying)
Ability to remove a thread, no loner of interest (even if I have replied in it)
Then I want good editing tools. This typing box is far too small. On the old one at least I could resize the box (but I had to do it every time). I can "hide preview" to make it the full width of my screen, but on a wide-screen that makes it hard to read too! Taller (or auto-growing on long messages, or via a CONFIG option) would help me.
EDIT: I've now found the thumb-tack to pull the edit box taller. Will be interesting to see if it retains that as a "preference" (couldn't find a Fingers Crossed emoticon )
EDIT2: Hiding the Preview is persistent, increasing the height of reply box doesn't seem to be. Not sure it bothers me having to increase it WHEN I need to ... but if it does I'll report back ... of course!
I haven't tried much in the way of replying yet, but I'll be interested to see how Quoting and [CODE] tagging etc. work. The QUOTE I tried quoted the whole post (much like the old forum of course). On newer forum software I used (on other, non-SQL forums) they have the ability to highlight text in the original post and then a "Quote" popup appears. It is thus possible to quote several fragments from user(s) previous post(s), which I have found very efficient when replying. No idea what plugins etc. are available for Discourse, so just talking out-loud in case any of my thoughts are useful.
EDIT: Yeah, well I should have tried it first, eh? Just highlight some text in a previous post and popup appears. If not already constructing a reply then the popup say REPLY and it opens REPLY box with highlighted text quoted, if REPLY box already open it adds the quoted text to it. Great feature!
I'm dyslexic so probably more vexed by these things than others. Screen clutter (particularly moving adverts and the like, but also Signatures, Avatars and so on) means that the rate at which I can absorb and digest information on screen is hampered, so on normal forums I have all those turned off, and use Ad Blocks to get rid of any "Moving stuff"