It looks great and I am sure it will continue to thrive under your good care!
China dolls have a tendency to become weedy and leggy if not pruned back regularly. Yours is already at a point where you could consider pinching back new growth and keeping it at what I think is an ideal size for that location.
Normally growth would slow a bit in winter because the hours of daylight are shorter. However, you are growing yours under lights so there should not be any noticeable change in its growth.
China dolls are prone to mealybugs and spider mites, so be vigilant.
