What kind of budget? Cannondale Scalpel 29er is a rocket. Got last years Carbon 1. 23lb, plush and just so fast it feels like I’m cheating. Never thought a bike could go with so little effort, BUT, that then makes you go faster and faster and… then you are stuffed! Took a while for me to reign it in a bit on climbs.
In all honesty, it is easily 10% quicker than my old Cannondale Rush which was no slouch and was about 25lb. Did Bonty 12 hour solo and BBF 12 hour solo and it was amazing. Even managed a 4th place at BBF which I was stunned with so certanly capable of long rides in comfort.