Hello there,
It is true that Adorevia wasn't handled the best way there is no doubt about it, but for Starmaker's case is a little different. We always put some of the new content that is going to be on the update on the planned features and the thing is, stuff gets added out the blue because of "hey, this would be neat to have" mentality, which is another reason that makes it hard for Starmaker to have a kind of "progress bar".
In regard to how updates work, the last big update, and the transparency of when it will release or what progress has been done. While true that there could be some kind of advice about the progress of what has been done, that is kind of difficult without spoiling the content that is coming, and while there was a timeframe before, we have always advised that to be an estimate (I'm not discussing this topic again so let's leave it at that) and is a main reason why there's no date now. Starmaker content creation is different to a regular development, out of the blue something that Kal thinks would be nice to add shows up and then is more work to be done.
The last "big update" was 1.8B, yes this is not the regular, but it is in fact a big update. It brought multiple scenes, minigames, locations, new character and the reworks of more scenes, and NO, this is not "content that was planned and couldn't make it to initial 1.8", is brand new content that Kal wanted to put in game due to the time it was taking to get 1.8B out. The reworked scenes even though were planned, did not include the ones done for 1.8B, all updates more and more reworked scenes are done to match the new style. So yes, is around 3 months since the last "big update".