>>> Do I just need to stop dithering and get on with it??
Probably yes!
However there's no particular reason to remove the Epson software anyway (other than freeing up a bit of space on your hard drive which, with the large drives that come as standard these days, isn't going to make much difference). If you're worried, simply leave the Epson software installed. It won't conflict in any way with the software for your Canon printer. (Installing the Canon software will almost certainly set your Canon model as the default printer. If not, simply go to Start > Devices and Printers, right-click on the icon for your new printer and select 'Set as default printer'. You can also remove your Epson printer from the list through right-clicking on it there as well).