Allow for more advanced maneuvers with elytra(loops & barrel rolls)

Sometimes you might try to do tricks on an elytra but find it hard or impossible to make barrel rolls or loops(you know, the fun stuff that planes sometimes do). The elytra should allow for the player to make more advanced movements when flying/gliding with the elytra, such as roll and pitch, allowing for the player to fly upside-down, do barrel rolls, or do loops. 

For the pitch, you could simply remove the constraint on how high and low the camera can turn up and down while using the elytra, which normally stops the player from having an upside-down view and a very unnatural looking head rotation. (of course the camera will be normal when the player is no flying/gliding)

For the roll, the player could use A and D, or some other keys such as Z and C, to control their roll. (The roll part sounds less Minecrafty so adding roll is less important compared to the pitch in my opinion)

Maybe there could be a minimum speed, altitude, or time in the air to perform a roll or go upside-down. Maybe you should have been flying for a few seconds to be able to roll, so you don't just activate your elytra and then accidentally start rolling. 

Additionally, if the player goes upside-down and has trouble getting upright again, after a few seconds they could automatically roll back so they're no longer upside-down. This could be a toggleable accessibility feature defaulted to off. 

Just think of how fun it would be to do loops and barrel rolls around a elytra course, or watch a minecraft airshow.