Typical Attack/release timing for mic compressor to use as presets 1-10

i have designed and, am currently using a mic mixer controlled VIA USB and software interface. The compressors work well, I saved several curves, that can be selected as presets. adding curve editor to my software would have been too difficult, and for the typical user would be "too much information" (imo). along with my preset curves i have added an attack time setting and post gain control. post gain controls set +/- 10db the attack i have as a 1-10 user setting.

1) anyone know from a practical live mic mixing situation, what would be 10 preset values for Attack and release?

2) what would be the min/max usable DB/s attack?

3) would my steps from 1-10 be linear from min to max?

4)what should the decay DB/s be relative to attack DB/s?