Nice avoidance of inscribing the roman reference. How does the piece feel density-wise compared to a bakelite-style set?
As an aside, what rules family do you use? (Since that affects bonus pieces needed.) I originally learned Riichi while living in Japan, but later switched to Zung Jung. (My compact reference card below.)
https://boardgamegeek.com/filepage/66851/zung-jungtm-compact-patternscoring-reference-card