Ghorpm: I also like to compare everything to colors (...)
That's AWESOME :D!
Would Heroes 3 count as blue or purple? Or something else entirely?
As a side-note, I think I've come up with a solution to this numerical conundrum, although implementation and using such a system would be pretty quaint:
Imagine a 2D board with 5 "helper" zones that can be as small or large as we want. Zones are aligned vertically, with 1 at the bottom and 5 on top. When a person rates a game, it goes into the corresponding zone. If there are already games present in that zone, the person can choose to put it ABOVE (better), BELOW (worse) or ASIDE (comparable) of any title he chooses to. Hell - the zones could even be eliminated at some point or even never be there in the first place.
Given enough people and some clever number-crunching, we could calculate the global, transitive intuitions on what is "better"... except that this doesn't some the problem of incomparable titles, which your coloring methods seems to achieve.
Perhaps different categories should be rated separately, when applicable...? OTOH - we've already seen this approach in game reviews and it doesn't really work all that well :\. The last thing that comes to mind are some "tags", which reminds me of how Gamespot deals with the issue.
Meh. I guess personally solving something that has been troubling people for decades is harder than I have expected...