Coffee Appreciation

For the first point (disclaimer, I've not had much experience switching between double and single baskets, so take this with a pinch of salt), yes, if you reduce the dose of coffee for a single, you'll need to make the grind much finer for an equal extraction. Though re-reading your post, are you keeping the dose the same between the single and double baskets? Baskets will generally come with a recommended dose, I'd recommend sticking with the double which will likely be somewhere in the region of 16-18g.

For the second point, it'll take practice, but the main points are:

• Start with the steam tip a cm or so under the surface of the milk, near the edge of the jug and pointing down and at a tangent to the surface of the jug. This picture is a pretty good example:
  
  

That'll ensure the milk is constantly mixing which should help prevent a cap of froth developing.

• Once the milk starts spinning, bring the tip to the surface until you hear that shh shh shh noise. Careful not to bring it up too high above the surface otherwise you'll just launch milk everywhere.

• Depending on how much milk you're steaming and how much foam you want, leave it there for anywhere between 3-6 seconds (rough estimate, you'll find what works for you) to create the foam.

• Sink the tip back under the surface of the milk to continue heating it without adding foam. Keep this going until the milk gets to the desired temp (a good starting point is to wait until the jug is too hot to hold, then iterate from there to find the right temp for your preference)

always seem to end up with a cap of over-foamed milk that then pours first, so latte-art (although not important for taste) is not an option

Foam the milk with the wand at the top of the milk, then drop it down below the surface to continue heating once you have the desired amount of foam. Have the wand at an angle so it swirls the milk and breaks up the bigger bubbles into a soft foam.

You'll need to keep swirling the jug continuously after foaming to keep the head of foam mobile, then it'll get carried out with the milk as it pours. When I've watched baristas do it well, they often do more milk than they need and dump the excess. I'm not into that as I don't like waste, so I tend to do what I need and scrape any stuck foam into the top. Current fashion for cappucino is to have crema round the edge and white foam in the middle, not latte art. My method is compatible with that so I'm happy with that!

On the baskets, i think posh baskets, like IMS precision, are specifically tuned so you don't need to change grind setting - i.e. the single IMS basket will create more pressure from the basket to mimic the extra pressure of the coffee in the double IMS basket. I imagine the same care has not been taken on the stock baskets that come with a machine.

I'm shit at latte art, but here are my tips for once you've got some passable textured milk.

You need a decent shot of coffee to pour into with a decent crema. Some beans are better than others for this I've found. Generally, using relatively fresh espresso roasted beans from a decent source is a good start.

Give the coffee a swirl in the cup before you pour. And give the milk a little swirl and tap on the counter too - just so you look like you know what you're doing.

Start pouring, but then lift the pitcher up so the milk falls from height - this makes it sink below the crema. Move the pour around the cup to keep/create a nice smooth crema on top.

Once you're over halfway, stop. Tilt the cup on it's side a little and start again with the pitcher nearer the cup. Give a decent splosh, slow down and try and let the milk float on top. A bit of side to side wiggling as you draw the pitcher to the edge, and then run it back up the middle should create something that looks a little bit like a leaf/corn head.

I still mess most of mine up, but doing more over lockdown has helped. Still baffled by people who can paint pictures across their flat white.