I noticed that, after a good enough start, HE has slowed down a lot. This is a real pity. What could we do to get more submissions, traffic... life?
I'll open with one imho important suggestion: Copy the karma system from HN. I understand the good intentions behind the choice not to have a rating system, but one of the causes of the lack of engagement with the website is imho in the absence of the gamification that karma brings with itself. Moreover, if HE will become successful and spammers and trolls will come, I'm pretty sure that karma based permissions will become necessary anyway.
Second suggestion: Use the Twitter profile (and maybe a Facebook and G+ page) to promote the best stories and create conversations where the people already is. Promote that/those profiles here on HE.
Third suggestion: Better branding. I already suggested using the .eu domain (that the creators of the website already own afaik) instead of the .com one; maybe we could also find a designer to create a more to-the-point logo. The obvious idea would be to to use the EU flag (or just the colors, stars) somehow, which would be very well recognizable but with the drawback that it doesn't represent all of Europe.
Any more ideas? Feedback?