I think the Bass Station 2 envelopes are plenty fast. They pop at the fastest settings.

There is a nice trick for extra envelopes if you are not happy with the ADSRs. You can set either or both of the LFOs to zero speed where they come to stop and then use the LFO delay as an envelope decay stage with a different curve from the ADSRs. You can also add LFO slew for some attack.

You can use that trick along with the ADSRs to access more range and also create multistage envelopes. You probably want to use the square wave and set the LFO keysync on to keep it consistent, but you could also set it to sample and hold mode to create some interesting variation.

Interestingly enough, you can use the LFOs as envelopes and with the latest updates, use the repeating envelopes as LFOs. I suppose that could be handy if you wanted an LFO with velocity control or something.