Some say the 5 and 5 rule is necessary for a perfect shot;
Drink within 5 days of roasting, and brew within 5 minutes of grinding.
I am a bit more relaxed but won't push it beyond 10/10.

The grinder is the heart of the whole operation and must not be underestimated.
I personally tend to roast into second crack and like a dark roast for my espresso.
I have tried lots of s/o (single origin) beans as well as lots of blends, but seem to always come back to the South and Central American ones for my go to beans.