Bit drastic replacing your bike due to poor brake performance. For the rear, Deore Vs are stiff as anything and only cost around a tenner. Couple them with a decent pad (Rock V pads, Koolstop salmons.), keep your current lever and you got yourself a cheeky little setup for around 20 quid. Not seen phase frames so not sure how much flex is in there. But maybe stiffen the back up with a cheap booster. Stick with it bro.