I believe @Nicolas has a number of gamification plugins that are quite helpful 😄
For the second question, you'll want to create or customise an existing theme so that the topic layout is vertical.
Is there any way to see how many posts were added in a specific date range?
We only show last day,week, month on the dashboard. I think we should allow a bit more flexibility to see any date range.
In the meantime this will give you the number of posts created between
db.sortedSetCount('posts:pid', min, max, callback);
max with a unix timestamp in milliseconds.
I mention that here, too: https://community.nodebb.org/topic/13972/