We eventually gave up on using the 58mm basket.
We went for the Bambino Plus and we purchased a non pressurized single shot basket.

Second day using it with BG Coffee Inverno and we are quite pleased with it.
We just need a better temper.

Does that steam want get used? There's not much room between it & the wall.

Not so far. With the Gaggia we used to make espresso only, no milk. But even if this changes it would be just a matter of moving it slightly from the wall and it is super light. Maybe not even that., with the Bambino you leave the pitcher on the tray and it does it all automatically.
Now it is leaning on the wall so that you need one hand only to insert the portafilter.

Probably could have just gone with the Bambino instead if you don't need milk. The whole point of the plus is it froths the milk for you

You are correct. We chose the Plus because of the preinfusion without knowing that the Bambino actually uses the same system for the espresso. So you are right, the Bambino would have been enough for our needs.

After five months of use and about 20 pounds of coffee, I can say that the Bambino has been working flawlessly. We drink only Buongiorno Inverno, and the Bambino has been very consistent, shot after shot. Performance wise, definitely an upgrade from the Gaggia. I cannot say anything about the ability to froth the milk since we are still not using it.

I was thinking about buy a classic pro or a bambino plus, but after your post i think will buy a sage for espresso and cappuccino! Thanks so much, is so helpful for me!

We have passed 2500 shots with the Bambino Plus. Still zero issues and very consistent. It would be nice to have the possibility to set the temperature, just to play a little bit with it, but the factory setting works well with Buongiorno Inverno.
I want to praise the Smart Grinder Pro as well, that we purchased in may 2019 and based on the orders we have placed since, it has run more than 130 lb of dark roast beans. I don't know when and if we will have to replace the burrs or buy a new grinder but so far it has worked well for us.
At the office we drink only one blend, no need for experimenting with "fancy" coffees, and for doing that this setup has been working extremely well.
The fact that with the Bambino you can pull an espresso within few seconds from when you turn it on, is major plus.