Pretty much everything you’ve said is the exact opposite of my experience (BMW 1-series F20 125i).

Great throttle response, minimal turbo lag, precise steering, and highly controllable confidence inspiring brakes.

I can see why someone might not like the shifter and indicator stalk, but they simply haven’t been an issue for me. In fact there’s aspects of them which I prefer.

I have driven the X1 and various other BMWs. The X1 is indeed horrible, and there is a reason:

For handling / lateral dynamics: The X1 is derived from essentially a MINI platform which is FWD-based (transverse engine), compared to the rest of the BMW lineup which is RWD-based (longitudinal engine).

For power / longitudinal dynamics: If GP happened to be driving a 3-cylinder, then of course the turbo lag would be high. OTOH, the 4-cylinder B48 is a venerable engine with negligible lag (again used all across the BMW lineup).

Its on a mini platform? No wonder its so small.

Thats what I get for asking AVIS for a large SUV/minivan for a family of 5 - my older daughters riding without a booster seat, wont fit.

It comes base with a three cylinder option? I want to cry. Every merge requires flooring the pedal and a prayer.

On one trip to the UK my rental car was a Mercedes A160 diesel. It was so utterly devoid of power that it was a legitimate death trap when confronting a busy roundabout from a standstill.

European automotive luxury means getting the perfect car from a wide array of choices, including the privilege of being able to choose an engine that makes an economy Toyota hatchback seem downright sporty by comparison.

I'm not sure if you drove in the UK much, but generally roundabouts are explicitly not "death traps" regardless of the amount of power you have. I literally use them on a cycle from time to time. Everyone is slow, pays attention, and is ready to brake if needed. If you feel need for extra power, you're probably doing something wrong (e.g. not giving enough space for the oncoming traffic you're supposed to yield to).

That is certainly the case for the vast majority of roundabouts. But there are also a number of roundabouts which have a large diameter, limited visibility and a continuous flow of fast-moving traffic and you’d be sitting there forever if you couldn’t nip into a small gap. I’ve noticed this in particular while in Kent in the south-east.

(I’ve driven across a decent amount of the UK, from Heathrow to Durham, Edinburgh, King’s Lynn, Greater London and Folkestone. I have an extended array of in-laws in Consett, Snettisham, Isle of Man, and elsewhere.)

I suspected that might be the case; I've driven an array of BMW models but haven't driven any BMW/Mini FWD architecture cars.

Maybe throttle response/automatic transmission/turbo lag isn't completely predictable across the same models? That would be disturbing.

I know that for example turbodiesels (even newish ones) start off pretty snappy but then turbo lag and other lags creep in.

Does the car say at which factory it was built?