I agree with using the word 'provisional' too instead of 0.
Although both have the same effects, really: that of placing your rating at the bottom of the leaderboard.
Another way maybe would be to display the word provisional, but then also display the rating that GLIXARE would provide you if your RD wasn't too high. This wouldn't be done on the leaderboard, but rather in the program itself. Something like:
Rating: Provisional (63.44%)
This would be done so that the player would know how he's doing approximately.
Also recall that glicko-2 increases the RD of a player that is not playing. If this becomes too high, his rating would become provisional, which, in my opinion, is a good thing.
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