The Short Sterling was eventually removed from combat and used to tow gliders.
Because it was ugly if nothing else.
Yep. Like a lot of the Brit bomber types, it had sufficient utility value to linger on in unintended roles. I have run across a few memoirs where pilots thought the Stirling was a good airplane that simply wasn't given enough wing to do its intended job. Unlike the failed Manchester which became the famed Lancaster, the Stirling didn't get a second chance.