I am also a CTO for a small startup in Seattle. We now have an engineering team of 4 and I find myself oscillating between playing these roles. At this stage, I have to make sure I don't ignore either position.
If I ignore coding, I begin to feel detached from the product we are developing. It becomes easy to lose interest in the quality of what is being produced. On the other hand if I ignore the managing aspect, we become a much less effective team.
Sometime later this year we will be growing and I wonder if and when it will be appropriate to drop coding altogether and start developing my management skills with 100% focus.