I don't know if it's too late to make anymore suggestions before the release but if not my list is short. Most of them relate to the cutscenes, which for the most part are excellent, but a few of them raise questions in the critical viewer's mind. Why didn't the old man use that little spy-glass on his cane to view the girl in her prison from on top of the tower in the distance? At the conclusion of the first boss battle, it seems like they should be running a little more desperately towards the open door, with the queen just behind them, ready to attack again when she's finished with the bird. And at the end of the final boss battle, the queen's face looks a little distorted; almost cartoony, which makes it hard to take that scene seriously.
Some of the cutscenes for me raise more questions than answers, like "What's with the old man and the bird?" "where are all the people?" "who built all those robots?" Others cause emotion to be better conveyed now that I know what's going on. Now I can see when the girl picked up the necklace, it may have reminded her of her mother. It's like I've been dropped off near the climax of a story I mostly missed and have to figure out what I missed as I go. Clearly there is some antagonistic history between her and the queen. The most puzzling scene for me has to be the ending. All I can conclude is, unless there's some secret ending I'm missing, this isn't over. And if/when you start working on the next installment of this game, I want to know, because I'll be there to Kickstart it in a heartbeat. And I must say I've enjoyed playing this game in small bites over the months, giving my imagination time to run wild before the next piece of the story is revealed, more than I would have if I'd bought and played it all at once.
As for technical and gameplay issues, I didn't find any on my initial play-through; just some minor clipping you expect to find in games, and the maze and catacomb under the queen's castle seemed harder than before; that may have just been game-fatigue though from playing for 3 hours.
I look forward to the release of the game at last, and to whatever you have planned for the future.