Garage Sub-Panel Addition
You have to provision 50A for the 10kw heater.  We can play some provisioning games on the saw, dust collector, freezer, lights and receps, and allocate them, say, 25-30A.  Which puts us at 75-80A.  

You could get away with #4Cu / #2Al wire.  However, there's very little cost difference just go go all the way to 100A, and that's commonly done. 

So, provision 1 AWG aluminum THWN-2 wires with a ground wire of 8 AWG copper bare or 6 AWG Al insulated.   There's no reason for a wire size bump at 80'.  

This setup would also have the reserve to stick a Tesla charger in there, though Tesla+heater+shop tools simultaneously would be a no-go.  Presumably you don't want sawdust on your car :) 

1-1/4" conduit should get it done. 

Our standard advice is to use a much larger subpanel than you'd ever imagine needing.  That's because "buying a subpanel with more spaces" will set you back a couple of Frappucinos, but "having to change your subpanel because you thought too small" is a solid day of work. If the subpanel is attached, even with a breezeway, you don't need a "main breaker" in the subpanel.  If detached, you need some kind of shutoff switch, and using a main-breaker panel will only add $20-30 to the cost of the panel.  There's no need for the subpanel size to match the feed breaker (100A) size, so feel free to get a 150A-bussed panel with a 125A main breaker if it's on sale :)  Also consider "value pack" panels that come with some breakers.