Well the DK in wow was added even though there was no balance in the classes :P
They just keep passing the 'overpowered' stick to another class....
In an MMO where situations chance due to development its only to be expected that there are balance issues =( Although i agree that at this point its a real mess for DBO.
Well you could consider that adding a new class into the mix might prove to make it EASIER to balance things.... It all depends on how the class is going to work whether it'd simplify or complicate things....
There's been speculation that its based on a capsule corp/bulma arch-type, so utilizing machines, guns, robots, capsules. But thats about it.
Well and the stuff thats been taken from the files like the names.
There's also some screenshots where you see that the basic weapon will be a small sort of laser gun like you see on some of the robots you encounter in the game. But i guess even that has never been verified as proof of the engineerclass.
I think it ll be the same. since those weapons use your ki to shot( just like the frieza soldiers) , I think they ll be so strong as a martial artist or a spiritualist.They'll go super Saiyan for sure.
But if you think about it that is kinda lazy to make the super form of someone who primarily uses weapons the same super as ones who have trained fighting. If you get where im coming from