There's a fundamental problem in that we can't do any sort of formal judging procedure (the only real judging procedure we do is the showcase, which is created in a fairly arbitrary manner), and so creating a reward that actually had an assigned value is never going to be fair. There's no getting around this. The medal can only really exist because all it is is a participation pin, anything more than that and we're back to square one.
The rule about eliminating low quality work would exist mostly just to scare people into trying harder. Plus, deciding whether or not an entry counts is already an arbitrary process (as earlier stated, it has to be), so we'd just use it as a caveat so that we can exclude entries that we know for certain are low effort. When in doubt, the entry counts.