Complete curveball (and I'm biased because I've ordered one), but what about the Tesla Model Y? It'll be circa £17k more than the budgets you've listed but you won't pay £500/year road tax, will probably save £2k/year in fuel and will likely be slow to depreciate versus the bubble that used car prices are in at the moment.
It won't have the 6 cylinder but has the 350bhp, boot(s), panoramic roof and adaptive cruise.
It won't have the 6 cylinder but has the 350bhp, boot(s), panoramic roof and adaptive cruise.