As most players use 16:9 or other widescreen aspect ratios, I won't object to hitobjects that are partially offscreen on the x axis. Partially offscreen on the y axis is not something I would appreciate.Agreed. This is something I was planning to bring up later. Thank you for pointing this out.
To be sure we're on the same page, objects that are partially offscreen on the top/bottom of the screen will be in the same position regardless of aspect ratio. On the other hand, if an object is partially offscreen on the left/right side of the screen, it's position relative to the edge of the screen will differ on different aspect ratios. Because of this, only the top/bottom sides of the screen should be used for partially off-screen objects to avoid discrepancies