Mic settings are automatically stored.
I generally use the automatic processing. Seems to work great. I use different percentages with different mics, according to what I'm hearing. Seems as if it is usually around 40 percent. I have experimented with various Gate and Compressor settings, but automatic is pretty good there too. You may not need to use Compressor but if you do, and don't use automatic setting, I wouldn't go over 3:1.
I think I'm using Large Hall reverb. Not in front of it right now.
Remember that the overall e.q. also affects the mic's sound.
Be aware that it is easy to overdo things when you have the overall e.q., mic e.q., reverb, delay, compression, gate, de-esser. Start very simple, make changes and see if they help or hurt!
With the AKG mic you are getting, I used automatic processing at 40 percent and it sounded great to me.
On my overall keyboard I have the MAXX Audio Bass and Treble at about 40, stereo and volume at 100. Overall e.q. is nearly flat with just a very slight, maybe 2 db, high end boost at 7500. Yours may vary depending on the venue and your own preferences.