Reliable high MPG hatchback under £10k?

I bought a Corsa 10 months ago. Done 12k miles since, mostly motorway (200+ miles a week). It’s now racking up costly repairs so I’m looking to move on.

Need something reliable, not to expensive to insure with good MPG, diesel or petrol, budget is £10k max. Planning to keep it a few years and rack up miles.

Been looking at leon, golf, Audi so far… are better options out there?

TLDR: Need a solid commuter under £10k that won’t break down. 200 miles/week, mainly motorway. What’s good?