My opinion is skewed though, as I have only had Cheap Bikes since I started riding seriously (and they’ve not hindered me whatsoever), so find it hard to recommend something spendy.
I think the main thing really is to buy something you actually want to ride.
Have you thought about buying a frame and building it up? How about Bowman Palace:R? £745 for the frame. Plasticmike rides one, they’re absolutely beautiful imho.