Hi GB & welcome. Ok, my take on your questions............but it is mine only, not gospel.
1. I include the crema in the 60ml. Beans may be too fresh & the crema is unstable.
2.Yep, one of the reasons to roast your own.
3.Nah, different beans for me all the time.
4.Blonding, yes & yes.
5.not sure here but would believe it is because there is no rim for your grounds to get caught up in.