At the moment a chloroplast weighs the same as body, and adds the same radius as body as well, but I am thinking about upping that, probably doubling it.
For them to be disadvantageous enough for 'animal' to be a viable evolutionary strategy I would start at more like 10x body in terms of mass and volume. I think if anything we should overshoot the value and then scale it back. Write some reasonable complex veggies and put them in league fights. If they decimate the animal bots, scale up body and mass some more. You could also do a bot against a veggy version of itself (where maybe 90% of excess energy is put towards chloroplasts instead of body).
For comparison to real life, plant cells are somewhere between 2 and 3 times as large as animal cells.
Poll