skylark I have no idea. I just take as it comes to be honest. These machines, grinders and the human behind them are not highly precision devices. There’s a lot going on.
I used to have an E61 and he second shot was always quicker than the first one. Go figure.
My advice to you is, unless you are unhappy with your machine, take the time to get to know it and enjoy it. Key in all the settings from DavecUK, and then stop using any of the features: no pressure-infusion, no this and no that. Just a straight shot. Do that for a couple of weeks. Adjust the temperature up by 5 degrees, than lower by 5 degrees and see if there’s a difference. See what you like the best, adjust the temp accordingly.
Then go about and enable all the features, one at a time.
If you are unhappy with it overall, which at think you are, then just sell it and buy what you want.
As for the lack of crema, all I can say is that pretty much anything from CoffeeCompass will produce a lot of crema. They are roasted on the darker side too. If you are not getting the crema you want, then please share a video of you pulling that shot into a espresso glass or cup, and show what do you mean by the lack of it.
Good luck.
Edit: for reference:
From Foundry. You won’t get tons of crema with this coffee, as it’s a medium/light roast. That was 18.5g in, 45g out in 36 seconds. Temperature set at 94C, 10s bloom pre-infusion.