Hi all - where to live?

Hi everyone - this is a long shot but Id like peoples opinions on best place to live along the northern train line from

FINSBURY PARK > STEVENAGE

There are places like Potters Bar, Hatfield, and Welwyn Green which sound ok but I have no idea what amenities are at these locations. Which place is most interesting?
Im 29, I also play squash.

Thanks
Graham

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