SureFire (or PK, perhaps more accurately) used to experiment with producing quite a few models in a range of colours. Some of these lights were sold in limited numbers through dealers, others were given away to friends as gifts, and still others were given to CPF as gifts for give-aways.
For better or for worse, SureFire is a much bigger entity now than it was back then, and these colourful experiments have been one of the casualties of an increase in size and workload.
The 30th anniversary E1B/EWP-01 set is evidence that SureFire still dabbles with special/limited editions from time to time, albeit in a different way.
ICON is a different beast altogether, and we're far more likely to see PK releasing different colour and limited edition ICONs than SureFires. The Rogue may appear in different colours (as a matter of standard production) if demand from dealers is sufficient. PK has already experimented with a wide range of different colour possibilities for the Modus - he has even posted some of them here on CPF.
ICON places an emphasis on aesthetics, and this simultaneously makes seeing interesting colours (beyond black and grey) more likely, but also more difficult as every product has to "fit" with the rest of the lineup. For example, the Rogues have already established a colour palette of green/grey/black, and any potential fourth colour would have to look at home with the others.
One way or another, I'm certainly in favour of seeing some more colour in our choice of flashlights beyond one-offs, small runs and limited editions.
Regards,
Tempest