FFMPEG encoder/settings for TEXT-LEGIBILITY and low file size? I often create long screen-recordings of myself explaining code.

When scrolling text, the movement doesn't need to be amazing, just smooth enough.
When static, the edges of text must be very crisp for legibility.

I'd love to be able to REALLY compress these videos down, as they tend to be quite long

I tried using CRF (Constant Rate Factor) but the trade-off space does not get me the size compression I believe is possible.

I'd be particularly interested in an encoder that could be "motion-aware". 
e.g. if the video is static, the encoder won't update the f. But if there is movement in the video, start storing frames etc. There is a freeze filter in the new version, but it looks like its for notifications only.

Does anyone have any good encoders (or settings) they can recommend?

Thanks
Most codecs are motion aware. The problem you are most likely encountering is too many key frames. Every time a key frame is inserted, the encoder forgets everything and starts over. If you set your keyframe interval very high, (like 60 seconds) the bitrate will be progressively lower over time, until the next keyframe.