In your position, I would go with an independent contractor setup, particularly since 1) you don't have a separate business office and 2) there is a seasonality involved in your line of work that may frustrate a W-2 employee. ICs understand slow periods and make other arrangements in the slow time.
I understand the desire to keep tabs on hours. This is a risk you take when you take on associates who aren't working in the same building as you are, whether they are employees or ICs.
Have you thought about an electronic time sheet application? This one lets you clock in from any computer or cell phone. (There are a bunch of others out there, but they're meant for larger operations.) That or something similar may help you with the time tracking worries.

