Engine improves with mileage

l've never done more than 65mph in our Jimny, don't see the point really
That's the speed my 110 likes to cruise at so l am used to it, doesn't make much difference to arrival times and it's a lot more relaxing than hammering down the outside lane ten feet behind the Audi that won't move over.

Ours has done 1500 miles and it is a lot less boomy on the motorway. Can cruise at 70 without going mad now.

The gearchange on mine was a little truculent to begin with, which was a surprise as the Gen4s I'd driven before all had a sweet action. Engaging first from a standstill was often particularly tricky.

Over time it's loosened up nicely to the point that it's now as fluid as I remember on those first drives.

I have noticed that the engine feels like it has a lot more torque after 1000 miles, I am hoping it loosens up even more after another couple of thousand..

It's quite normal. It's partly due to everything "bedding in". Wear is highest in the initial stages of using an engine, and they are manufactured in such a way that the engine reaches it's optimum once this wear has taken place.
Another not insignificant factor is the human one. Over time you learn how to drive the car. Most of it is subconcious. Builiding up muscle memories makes you a smoother operator, you ear becomes attuned to the noises that matter and blanks ot the ones that don't and you adapt to how the car likes to be driven.

Yes l need to get used to driving a 16v petrol engine, after driving a Land Rover diesel that red lines at 4,500rpm and rarely needs to go over 2,500.

By the time you reach the maximum power in the Jimny it sounds like the pistons want to escape from the engine block.

Although it's surprisingly good when driven like a Land Rover, not exceeding 2,500rpm