Thanks. I have seen and tried hts, I was surprised with poor results and long computation times. This could have been due to the structure I put them in. I know that it is often recommended to put stores in geographical groups, but there could be other potentially better groups that I have not looked at yet such as population size or surrounding demographics.
Though I have combined many forecasts I have never used
forecastHybrid. Combining forecasts has been one of the more successful approaches. Again, this is just with the data I have seen. So if anyone is reading this for their own application test it on your own data.
Some of the other more successful approaches have been
auto.arima or a combination of the above. This does vary by frequency. I have found, for example, that one method works well for quarterly data while another for monthly and another for weekly.
If anyone is interested in digging into forecasting I highly recommend checking out Forecasting: Principles and Practice. The second edition just came out in April 2018.