Putting out the Print and Play and TTS version definitely helped us get the word out. At conventions I had people overhearing me talking about Danmaku and excitedly telling me they'd played the PnP, these were people I'd never spoken to online. On the other hand, because we got delayed a year though, the game ran its natural course for some players and I don't know if they'll be interested in buying the coming full release. Some people disliked the fact that we weren't giving our art out for free, but we went into this knowing it would be impossible to please everyone.
TTS itself is an OK platform for card games, it's slower than real life in a lot of ways. Remember that ZUN expressly forbids publishing Touhou derived works to any platform that isn't Sony, and the latter I believe you need permission for, similar to being a corporate partner instead of a doujin work. EDIT: Sorry I forget people don't know what this means. It means that you can't use the steam workshop to publish a game on TTS, you can distribute a save file though, it is a legal distinction because publishing to the workshop counts as publishing to Steam.