For cells with photosensitive ability (photosynthetic organelles, eye points), the degree to which light intensity affects activity is incorporated into cell behavior.
Gain or loss can be set, with no impact in the middle; The threshold, median, and upper and lower limits of the influence of light intensity.
Yes, I have thought about this as well.
Generalizing the base aspect too:
Also, something that cells don’t even seem to take into account and could for activity, is whether they are gaining energy balance or losing it. This could be not only ATP, but also glucose and other chemicals they can use to consume into ATP (such as Iron for rusticyanin).
Non-predatory cells losing energy should try to conserve energy by only moving as essential when they are on the losing end of the energy scale, instead of moving around because they can (and accelerating their deaths).
I believe this theoretical implementation takes into account photosynthesis as well.
To only take into account light level and not general energy would be detrimental to only partially photosynthetic cells (that would become sessile at night even if they have for example only partial light affinity). Taking into account overall energy would fix this.