Hi Dave,
A novel idea indeed with the usage of Linear regression for a Price Forecast. I 've seen that being used in research papers more often and never in real world use cases, probably because of the many flaws in forecasting.
For example, residuals and its corresponding plot could give us an idea of the fit better. R squared still suffers from the problems of spurious regression. An F test could help better in explaining the vailidity of the coefficients.
All in all, a very commendable effort! Good to read novel ideas and thoughts! Keep up the great work!