Extremely poor and brittle branch structure on a trident maple?

I was recently given a mature trident maple 'bonsai' in the hopes that i might be able to work some sort of wiring and styling miracle on it, though so far i've had pretty much nothing but dismal failures. The whole thing as far as i'm concerned is almost worthless as regards to ever becoming a great trident maple bonsai as it has an extremely bad case of inverse taper at its base leading up to a trunk with zero taper at all along its entire length.
Wiring at this point is also extremely difficult as its main trunk is about 2" thick whilst all of its branches are at least 10" long and 2mm and under thick as well as being very very brittle and almost impossible to bend without breaking. To make matters even more interesting all of these extremely long whips have no forks or extra branches coming off them, and at most have 1 or 2 pairs of leaves along their entire length...

I'm just wondering what i should do with it? graft new young branches on? try to get it to back bud and develop those? Or better yet hand it back and say i can't do anything with it?

Pictures will be added soon

We can't advise much that is specific until there are pictures, but I will say, you are fortunate that it is a trident. My guess is that you will be advised to air layer the trunk at some point to reduce the inverse taper. Then you will be advised to remove ALL of the branches and start over. Those two things will have to be done in stages, and it will take several years, but with a trident maple it is always do-able.