According to
Evans, the 2015 model of your bike has Tektro long drop calipers.
So, firstly, you need to be careful that the replacement brake is long drop too.
As others have said, try changing your pads (I always liked Fibrax X-treme, personally, but there's Koolstop Salmon and Swiss Stop Green that are similarly grippy).
My personal experience of the Tektro long drop brakes fitted to my Giant SCR2 as original equipment was that they were not great - and after several years trying different pads, I found that a set of R650 calipers made a significant difference. This is, however, a contraversial position;
https://www.cyclechat.net/threads/brake-upgrade-worth-it.177340/
Regardless, changing pads will cost you in the region of £7, and is worth doing first to see whether it makes enough of a difference for you.