I find that most juices hit harder when I vape for the first time on a morning. Are you experiencing harsh burning drags or just intense flavour drags? If its the former, have you let your cartos sit for a while after filling them to ensure the liquid has saturated through the filler? If its the latter it could be that the juice has collected around the coil. I find this happens with the kanger horizontal coils that I use and I get a much more intense couple of drags when I've let them sit for a while, but its not usually harsh, rather more flavourful.
I have to admit that I've only just received my first bottle of Bobas and I've been dripping it so far and find it an all round mellow vape.