Currently when legato is active every single modulator follows legato behavior. It would be quite handy to be able to exclude individual envs, LFOs and rands from legato, or at least exclude random LFOs from it. That’s the most useful case - say you have a S&H LFO frozen and it stops retriggering on noteon when legato is enabled. That’s often not wanted.
Optimally we would have three modes legato for each modulator: default, always, and exclude. Default would follow the synth global setting. Always would never retrigger as long as the voice has held notes. Exclude would always retrigger despite the global setting.
Why three? For convenience. Say you only want one LFO in legato mode. Now you don’t have to set the global legato and then exclude every other modulator, you can just set the retriggering mode individually.
Then if we get mono mode per modulator the behavior above would regard any playing voices.