I saw some of your videos on Facebook, and they’re absolutely stunning!
Unfortunately you’re right that there’s not really a way to post large videos on the BAA site currently. Basically, hosting video files comes with a whole load of additional complications (very large file sizes, different codec / container choices, the need to stream lower-resolution transcoded video files to mobile devices, etc, etc). We took a conscious decision when setting up the observation archive that hosting video would be an entirely different project from trying to host images. Inevitably, whatever quality setting we picked in the transcoder, I suspect half the BAA would complain the quality wasn’t high enough, meanwhile the other half would complain the files were too big to fit down their dodgy internet connections. 🙂
The facility to post animated GIFs was a compromise solution we added to allow small animations to be posted.
My recommendation would be that you upload the videos to YouTube, and then post a still-image from the video to your member album, with a link to the full video on YouTube? That way, we outsource the difficult video-streaming problem to YouTube. This is actually the same approach the BAA takes to hosting its meeting videos nowadays.