Those are absolutely beautiful!
I always pinch off all the flowers ASAP. Coleus not grown for the flowers. If the seeds set the plant's habit is to die because they have finished their purpose to reproduce.
Coleus do not come true to the parent plant, but if you let the seeds mature at the end of season save them and plant inside about February. You may get some unique plants that are your own new cultivar.
I used to have folks tell me to not look at a picture because it had flowers on it.
Sidney
