It also seems to me like your process is unnecessarily complicated. I've had pretty much 100% drinkable shots since after like the first 4 or 5 dialing-in shots and my partner who had zero barista experience has also been able to do the same on our mini. (From what I understand Micra might even be a touch more forgiving!) So here's what we do, in case it's of any help.

My beans are ordered from Barrington Coffee in MA. They roast Monday-Wednesday and ship same day. Over $50 gets you free shipping so I order several bags and when they arrive I freeze all but one. (I use a vacuum sealer/bags for this but not sure this step is strictly necessary!)

I use a lunar scale, tare the portifilter, and grind 14g directly into it. (Mignon grinder.)

I do a slight level with my finger sweeping the top, sometimes a slight tap on the counter, then I rotate a wedge distributor tool and give a quick tamp with the stock LM tamper.

Set the scale on the tray, place cup, tare and flip the paddle for 31-32 g. Stir and sip.

I've had the water run out before at 26g or forgotten to stop and ended up with 36g- all were drinkable! In addition, I have rarely enjoyed espresso at any establishment as much as what I routinely taste at home so I wouldn't necessarily agree that if you haven't liked it other places you won't like it at home. Sometimes it's so delicious that I feel like I can convert my coffee-agnostic friends if they would try it!

Anyway I hope you very quickly resolve your issues and start to get the repeatable results I've been at this point taking for granted for a year. I know you will succeed!

Should also mention that when I first got the machine, I watched this video and this is pretty much exactly the process I follow, in case watching someone do it is helpful. It was to me!
(This moves a bit slow, she starts demonstrating around 11:40, if you want to skip ahead!)

Thanks, Zoobee. It's been an interesting preliminary journey, for sure. By now, I've tried five or six types of coffee. Only two, Atomic Intensi and Rocketeer, were received within the optimal freshness window. I'd say that, other than crema volume, I haven't found the difference to be especially profound, but it is noticeable. At this point, I'd opt for "old" beans of a brew I like over fresh beans of one to which I'm indifferent.

Interesting that you also see my process as over complicated. Frankly, I don't see it that way at all. There are extra steps, but they're easy and and repeatable and the process is quick to execute...especially for someone who makes one a day on weekends and days when I don't need to be in the city. Curious what you see as truly unnecessary. Is it just WDT? I struggle to see how at worst, when properly executed, it could degrade a shot. The wedge would seem to be far more likely to lead to inconsistent results, as it essentially sweeps the top of the puck but seemingly does little to ensure consistent density at the base. Your mileage may vary and I'd obviously defer to your experience with it over my impression having watched just a few videos. I see the benefit over simply finger swiping, but not properly executed WDT.

In any event, the app says I've pulled 91 shots. I'd say five were of a caliber that I'd hand to someone without being embarrassed. My standards are, admittedly, exceptionally high, but I still blame the duh-rista.

I think I'm just especially picky about espresso and, under essentially all circumstances, would prefer a milk-based drink of some sort, even if it's just a macchiato to sweeten it up a bit. By now, I've pulled plenty of shots within "ideal" parameters and, lately, have been thinking one man's bitter or sour is another person's sweet spot. Or is that just what I'm telling myself to feel better?

My wife keeps asking me whether I think I've made a mistake. I reply with an emphatic, "No!" First of all, I've only had the machine for several weeks so there's plenty of time to improve. Second, I'm enjoying trying different coffees and aspire to nail a recipe and chase consistent results as the beans age. Third, and most importantly, even my bad shots make damn tasty flat whites or cappuccinos so the shot can't be that bad...and if it is, I sort of don't care. It would be nice, though, to be happy to offer a guest an espresso rather than try to talk them into something with steamed milk.

Having found that the steps on the 1zpresso K-Ultra are just too wide, I'm definitely looking forward to when the Zerno Z1 is delivered in August. I knew the J was a better fit for espresso, but bought the K which will be a better fit for my son once the Z1 arrives. There are times when I've been able to hit either side of the range and a middle step would fit the bill, but no such luck. In those instances, I've generally increased/decreased the dose by .25g or played around with the temp, typically in 2.5-degrees Fahrenheit increments.

I've wasted a fair amount of coffee, but learned a bunch along the way. Next up is a trio of espresso blends from Olympia Coffee (Big Truck, Morning Blend, and Little Buddy).

Thank you for sending the video. I'd watched several of her COVID specials while awaiting the arrival of my LMLu. They were very helpful. I really haven't found anything within my process to be problematic. I can't seem to bring myself to level by hand and tamp with the LM tamper when I've got the WDT and dosing funnel plus The Force tamper. The naked shots show no signs of channeling and the spent puck (always a small amount of water on top) feels consistent in terms of firmness. I do seem to see the screw impression after the puck expands, but only barely now that I've dosed down to 16g in an 18g VST basket. Sometimes I think I'm reading too much into the dent while others I'm convinced that area would be relatively under-extracted leading to over-extraction elsewhere. I arrived at 16g, at least with the two Atomic blends, after dosing down until I got to the point that the screw didn't dent the puck upon inserting the portafilter into the group head.

Thanks, again, for taking the time to offer your thoughts, advice, and recommendations.