@rafaellop for popover sizing lock at: Popover sizing as the popover contains a normal ion-content element it will be hard to auto size it, because it can have any type of content. Maybe an attribute in the ion-popover-view tag would be nice.
For positioning, I just tested in with a list and got to the same result as you, the popover should position it self based on the position on the screen. But this would result in the restriction that the popover never can have a size bigger than 50% of the screen.