Make the sub gift badges permanent.
If you gift 100 subs and they run out, your badge disappears forever unless you gift a sub every month. But if you gift 1 bit, in 5 years you will still have that (ugly) bit badge. That sounds unfair to me. Make the sub gift badges permanent, or make it so that it will stay 1 month for every sub gifted (so for 10 gifted subs get the 10 gift subs badge and keep it for 10 months).
Good point! Make it stay just like the Bit reward badge.
I thought they were already forever
Just a heads up, you can choose what badge(s) to display by clicking the cogwheel at the bottom of a chat and selecting your name under "Chat Identity". Hope this helps!