Other than that, your examples for the given categories should help to evaluate. Just note: a mono color deck may use just basics and have the most efficient manabase possible. That should be considered in the examples.
Yeah, I didn't take that into account... Maybe the scale is relevant to
gameplay, not the actual cards themselves.
0 - can produce mana
1 - can produce relevant colours one turn behind the curve
2 - can produce relevant colours one turn behind the curve and consistently
3 - can produce multiples of relevant colours immediately
4 - can produce multiples of relevant colours immediately and consistently
5 - can produce multiples of relevant colours immediately, consistently and has utility lands or above curve land ramp (e.g. Coffers,
Urborg,
City of Traitors,
Ancient Tomb)
Better? A monocolour deck with just basics will get a 4. A shock-fetch-ABUR-dual rainbow monstrosity will also get a 4.
Perhaps that's the key: we can quantify the differences if we talk about how quickly or effectively something can be achieved and if any of the categories contribute to that. A sort of "relative actions per round", if you will. That doesn't really care whether you're an infinite combo deck (if you discount the turn you win) or a heavy tax player (you can still make big effects per round compared to your opponents if they can't play anything).
And ok, 0-5 it is (scoring out of 6), I'm not going to argue about that.