Compromise: Mountain or street?

For the past few years I've owned an outdoor 'Blood dog 1800 j-series' and it's been doing absolutely fine, issue is that I've now got a new job and so my cycle path has changed.
Basically it's tarmac all the way until the last 5 minutes, where it gets kinda muddy and wet, particularly in these winter months.
My budget is around £500-£849 and I was just wondering if anyone has any good ideas for a compromise between a mountain bike and a fast, urban street one.

I'd be really grateful if you could recommend something, thanks a lot

Pedal.

PS - I can't take pics of it, my camera is broken but I've found one online that looks pretty similar to my own.



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