"White Text : Anything in white is my own invention. Sometimes this is just extrapolation - I guesstimated that the Nebula class has eight phaser arrays compared to the Galaxy classes twelve, for example, because the Nebula class is slightly smaller so probably slightly less powerful. But here and there I have gone into invention meltdown, inventing entire histories for ships about which we know little. Now and again I have even made up new backgrounds to known events just to make them sound a bit more dramatic. So be warned, if it's in white you can take it or leave it!"
We only know the ship exists...that's all.
And it's "canon", not "cannon"
*EDIT: you also forgot a ship I enjpy flying myself: the Akira AKA "Heavy Escort carrier"