With a kit like that, the variation is either in the fermentation or the bottling.
With fermentation, the temperature is likely to have made the biggest difference. Though, your description sounds about what you would expect.
Did you do this at different times of year (i.e. is room temperature different?)
After main fermentation (7 days-ish), it is best to keep it at a lower temperature (fridge temp) to condition for a couple of weeks. If you can move it to a different bucket for that it helps (just to clear it off the sediment in the first one). This will help make the beer clearer and taste nicer.
During bottling, you want to be consistent in the amount of sugar (best to mix sugar in a couple of hundred mls of water, then put that back in your first (sanitised!) bucket to blend. Then bottle and leave the bottles at room temp for 10-14 days as you are restarting fermentation (fermentation stalls at low temps).