It's fine, and I don't want to discourage feedback overall. It's just that an open-ended "I wish there was more" on a game that took nearly two years to finish has a lot of potential to rub someone the wrong way. But let's be clear, you are right in some ways. There are definitely weaknesses to the game: the combat is shallow, there isn't really any mechanical rpg progression, etc. I don't deny that, and I will try to improve that at least in small ways as I keep making games. But the improvements will probably focus on quality rather than quantity; this is about as much STUFF as I can probably get into a game, but I'll do what I can to improve how good it is as I go forward.
It is, and always will be a fairly simple RPG though, I want to be clear on that. I've played a few recently, RPGMaker games, that genuinely went on to 30+ hours, these vast, sprawling stories with all these different subplots and characters coming and going and this huge character mechanic progression where you start out simple and become a god by the end. Cruel Serenade will never be that. It's short and sweet, an episode of a Saturday morning cartoon for adults.
But there is always room for improvement, and I'll do what I can.