OS Image deployment - I use Clonezilla. Setup a VM with all needed drivers/applications for all devices in fleet, create and answer file, sysprep and go.

remote support - I include the access version of ScreenConnect in all of my images (see instructions on anonymizing the setup pre sysprep.

asset management - I use Excel, but SnipeIT I hear is good.

But of course, the three links you pointed to already say all of this.