easy upgrade of all sp_blitz-procs?
This is how I deploy them in my environment.
In SSMS, view Registered Servers, create a local server group called Staging and put all the Staging servers in there.
Right click on the Staging group and select New Query. This will open a new query window connected to all the servers in the group. Status bar will say Connected xx/yy where xx is the number of connected servers and yy is the total number of servers. 
In the Query Window, paste the sp_Blitz code and execute it.
This applies the proc to all the Staging servers at once.
Repeat the process for the other sp_Blitz procs.
Repeat the process for the Production group of servers.
It only takes a few minutes to deploy all the sp_Blitz procs to a large number of servers this way.