Adding Activitiesy

I'd like to add some activity or categories to the list of sports for more mundane things like snow shoveling, cutting the grass, etc. I have seen discussions saying for shoveling to use cardio and for something like cutting grass to use walking.  It seems like the category setting picks which sensors on the watch (or linked to the watch) to use. So something like cutting the grass would use heart rate and steps, working on construciton or home repair might use steps, heart rate, elevation for going up and down ladders), Maybe elevation for these things to as anyone in high elevations would have less oxygen.

I would like a way to create these categories by specific activity rather than simply cardio where they'd all get lumped together.

I can picture something like you enter a category name and pick which sensor data to use to calculate calories burned from a checkbox list. 

I also see there is custom sports categories available  from third parties which I assume you can import. I could live with that as well, but as of yet don't know where to get then, how much cost, etc.

Can anyone give me some guidance?

Thanks in advence