Keep one of a set of matching files

I often end up with 3-6 files for the same episode of a TV show, thanks to my automated downloader. They're all neatly renamed, thanks to Hazel, to something like "The.Walking.Dead.s03e14.mkv", "The.Walking.Dead.s03e14.mkv-2", "The.Walking.Dead.s03e14.mkv-3", etc.
Ideally I'd like to keep the file that used to have 1080 in the name over the one that used to have 720 in the name (and then only one of those – the most recent, since sometimes there are reposts – if there are multiple). Barring that, I'd like to keep the largest of the set, as a proxy for quality.
Any ideas? Very much obliged for the help!
Ideally I'd like to keep the file that used to have 1080 in the name over the one that used to have 720 in the name (and then only one of those – the most recent, since sometimes there are reposts – if there are multiple). Barring that, I'd like to keep the largest of the set, as a proxy for quality.
Any ideas? Very much obliged for the help!