Writing can look good if you separate it nicely and choose a good size.
Talk with your tattooartist, they're really good at making it aesthetically pleasing.
I have a quote from a Gackt song on my back like this;
I'm very happy with it, but at the same time I have 5 other tattoos that vary in size from wrist tatt to half my upper body. So if that will be your only tattoo, don't go overboard with colours and size, keep it slightly clean.
If i was you, i'd cut out 'そうじゃない' (so janai) because its not really that important for the meaning and it comes less of a clutter