Cool idea to do this, and a very successful first attempt! I have recently made a variety of time lapse video for my work (though I don't work making videos, it was very DIY/hobby/cheapo-style). They are fun to do, and a bit tricky to practice and get all the variables tuned for a particular type of shot.
I assume you are using single shots with a digital camera? Do you have the ability to run 2 cameras at once (for simultaneous overall and closeups)?
As stated by a previous poster, fewer frames to increase the speed significantly would make it more 'exciting'.
This gets tricky because you potentially loose slower details as you speed by them. I did have the opportunity to use pro software that easily manipulated the speed at any point in the clips, so experimented a lot with variable speed to precisely suit my needs. You could accomplish the same (tediously) by dropping frames.
The variable speed might be weird with the clock there slowing down and speeding up - or it might be cool. Once around the clock (12 hrs) in 1-second of real time might be a good pace to try for steady speed version, but experiment. I like the idea of the clock, but on a fermentation time-scale, you almost need a calendar rather than a clock. Maybe mark off days on a calendar so the video can go much faster?
A much lighter beer with a light background so you could see better. Especially if you don't care much for the final product, light it accordingly to make sure you can see into the beer well.
Closeups of:
vigurous churning in the middle
yeast at the bottom moving around
krausen doing its thing
airlock
For closeups, you can vary their speed to suit the action - editing them each at their own speed together will still flow well. Getting the natural speed of each individual shot/view just right is the most important part in general.
With video software, putting a 'close up' version in the corner while still showing the overall shot to bring in the close-up shots.
Overall super-fast start to finish to emphasize clear - to - cloudy - to - foaming - to clear transition.
Regarding your desire to temp-control. You could use a clear aquarium to submerge in water while still filming.
Just some thoughts, let me know if you want help with anything I mentioned.
Aaron