Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
I don't want to fill it totally though because otherwise I can't get any new apps.
 
Think about it this way, if only having 8GB free was detrimental how would that impact all the 16GB phones and iPads? I wouldn't let it get under 1GB but otherwise You should be fine.

True.

Must really suck for 16 GB phones and iPads.
 
i have a 16gb Air 2 with 4 gb left and its fine. My iPad is a consumption device so I can get away with it.
 
I have a 16gb Air 2 and I frequently have less than 1gb free and have never noticed a slow down.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.