Time added during practice
For other languages, it seems like it's typical that ten seconds are added to the timer on a correct answer. In Japanese, it seems like I've only been getting five, which makes things much more difficult, especially when I have to match a number of pairs or type a sentence (which I much prefer to constructing it from pieces). I have been timing out frequently during practices, where I find I rarely do with other languages, despite three years of classes in university.
I agree with your concerns.
Can't you just do untimed practice though? I wouldn't even think of doing timed practice on Japanese, especially given that it's a beta course. There are so many problems with the Japanese course, many of them not because of anything anyone is doing wrong, but just because it's a young course, like the vast numbers of valid alternate translations not yet accepted.
I wouldn't recommend anyone to do timed practice on Japanese in its current state unless they're specifically looking for an arbitrarily-tough challenge.