So run /usr/bin/scanimage to see what SANE reports from that backend.
It’s an alternative to iscan for the long run as well, although I hear ya that iscan package needs updating.
# list known scanners
# opts for one device using device-name from above
scanimage --help --device-name "foodevice:DEADBEEF_123456"
# test scan American letter size 8.5 by 11.0 inches (215.9 by 279.4 mm)
scanimage -d "foodevice:DEADBEEF_123456" --resolution=150 -x 215.9 -y 279.4 --format=jpeg >/tmp/scannedpic.jpg
Epson support site says the latest firmware on your model is
Release Date: 30-Oct-2014
Make sure that’s installed too.
If SANE works then GIMP has a GUI interface as well.