am saving for an aerobatic course in the summer
Why not do aerobatics in a glider? Even standard trainers do loops, chandelles and spins, many gliders allow rolls, and some are stunning aerobatic.
Gliding seems like an option, but I'm not convinced it would be worthwhile. My impression of gliding is flying round and round in circles while getting in the way of power pilots who are actually on their way somwehere.
It is said that people who transition from gliders to powered aircraft first have to learn that you can fly straight and level, and then have to find a way of staying awake while flying straight and level because it is soooo boring.
Try ridge running where you are eyeballing sheep on the hillside whilst avoiding the other half dozen craft doing the same.
YouTube - A Jolly Jaunt in the DG500 or
YouTube - What did you do today? YouTube - You Call That A Ridge!
Try "formation" flying behind a tug, or "loose formation" flying by sharing a thermal with other gliders.
I'm pretty sure I wouldn't be too popular going to a gliding club and saying that,
I expect they would have a slow, broad grin as they realised how much fun could be had demonstrating that your understanding is flawed. That's both you and them having fun
How long can you stay in the air?
I believe duration records were abandoned decades ago because it is unwise to fly when you are asleep. Nowadays it is limited by the hours of daylight.
Five hours is the shortest that is regarded as "interesting" (but certainly not remarkable).
Can you actually go somwhere?
Well, if you want to guarantee arriving at a particular place at a particular time, then I wouldn't use a glider.
But yes, they do go places (and usually return). For example, a few of last year's flights picked out more-or-less at random...
I think the nearest club to me would be based at Kenley.
See
British Gliding Association >> Find a Club >> UK Map for the full list.