SteemSTEM is a nice idea and I laud the efforts of the team!

To help improve post quality, I suggest building a dedicated website for SteemSTEM. The posts would still be visible on SteemIt, but can go through a process of review. Luckily, there is one open-source software that might be easily adapted for this purpose.

Utopian.io is a project that encourages open-source software development using the STEEM platform. People post about their open-source contributions and a team of moderators review these posts, suggest edits, and finally approve or reject the post at the end of review. In general, I think the quality of posts in utopian is pretty good.

The good news is that Utopian.io is itself open-source. So you could repurpose it for SteemSTEM with a bit of work.

Let me know if you would be interested in exploring this idea further.