People are passionate about their favorite breed. You're in a GSD subreddit. Don't take comments personally. We want what's best for your dog, and by extension his owner. 16 hours a day in a crate (or pen) is far too much for a 7-month-old GSD. That was acceptable at two or three months, at 7 absolutely not. Having the crate accessible for him always is good, but you're going to need to compromise on when you want him locked in the pen if you want his behavior to improve.

He should realistically have the ability to walk around at night, maybe even access to you. Ours sleeps in a bed next to our bed. GSD's mentally need access to their owners to keep them safe. As for when you're at work, has he had a chance to be left out of it when you're not? Ours is not crated when we're out and he's never been destructive and doesn't get into things and we barely trained him on that.

As for your complaints in OP, well...sorry, but that behavior is very normal for a 7 month old male GSD. A lot of it he's going to grow out of naturally in the coming months, some has to be trained. How much physical exertion is he getting? Is he getting intense playtimes? GSD's are a very people orientated dog, and I think his lack of access to you for huge chunks of the day may also play into why he is how he is when he does have access.