Vitus Sentier hardtail for £1k is one of the best options at rrp. Either 27.5 or 29er options I think.
Meant to be great fun and a good spec for the money.
Full suss then the Bossnut is probably the best rrp choice.
Might be worth looking to see what spec Sonder Transmitter you could get for that money too – although I think the Sentier has a more playful frame.
I did buy a Sentier myself as my hardtail (I have a Bird FS too) as I got a bargain frame and built it up with bits I had in the garage already plus a few bargains I got on eBay / CRC. Love it – so much fun.