I've been playing/testing the game since the earlist days of 0.200 and seeing how the game has changed fills me with joy. I cannot believe that's the same game (actually, it isn't anymore, too much has changed).
The Ui, one of the biggest complaints from my side, is so beautiful now. And a lot more understandable. I like the quick comparisations of weapons. It makes it easier for new players to decide what to pick, while experiecned players of course know how different weapons behave.
Also, unlike Isaac, you actually TELL players what each item does. My god, Isaac is so aweful with its items, it throws hundreds of them at you but does not explain a single one. Worst game explanation I've ever seen. There is not even a "learn by doing" curve because even testing does not entirely show, what an item does. Starward Rogue handles this a lot better and I'm sure players will appreciate this.
Gun control feels a lot better as in the first days, I rarely miss the enemy. That's mostly because of the laser sight, it helps targeting a lot.
Bosses are challening but never unfairm (I just suck at doging bullets), rooms are most of the time fairly strucured.
And you managed all this in such a short time, impressive. I'm sure when it comes out, Starward Rogue will be a great game.