I just found out that the delay time of the ADSRs are fixed. What a stupid mistake! I can link attack and release to whatever I want, but not delay. That's why hihats from STS never sounded believable. It's the same on the more complex second ADSR as well.
I think they should either make the delay variable, or have a switch button where you can switch between ADSR and AD envelopes. I mean, percussion instruments are mostly AD anyway.