Long post ;)
With out changing teh settings and playing a bit... The steam can be a slight pain...
Unless you mod it; but that is another story.
1: Coffee shot / Steam milk - Purge steam and then Purge / flush the group.
2: Then another short cooling flush and then ya ready for coffee number two.
3: Ya never mentioned teh beans your using ?
4: KKs steaming tip.. IS great but is not always so ideal with systems that do not have; that true full on steaming capacity.
Keep trying .... Thats what coffee is about.
As to how should it tast...
That is Pallet training and also not putting faith into others hands. It is about YOU, not THEM.
If its what you like, then great... Go and dry a few sponsors.. Try a few little shops and get ready to drink some dammed horrible crap... Then one will hit you and you will want to go back... That is teh one you want to try to copy..