Tall, thin and elegant bonsai appear to be out of fashion. There is a real emphasis on trunk width to tree height ratios, and that ratio also appears to be moving in a shorter fatter direction. To be fair I often try to design my bonsai with thick trunks and as short in stature as I can, but I do think there is a place for the tall thin examples.
The largest trees in the world would never make it as bonsai simply because they are far too tall in relation to their trunk thickness and the oldest trees in the world also fit in this category.
This plum is tall, skinny and I think elegant. It stands 115 cm tall and I have never done the measurements to determine the thunk width to tree height ratio because it would be pointless. The tree still needs a lot of work and the next phase is planned for just after leaf fall where most probably all branches will be wired (to take out those that are straight) and some other work around the trunk transition.
This English elm was dug by me a few years ago and it was pre-styled by horses who ate half the bark off the trunk almost all the way along the length of the trunk. This tree also needs a lot of work especially a new pot. It needs work on the nabari, work on the dead wood and probably a reduction in the size of the crown to bring it more in line with the literati look I am aiming for. Again it is tall, thin (probably not elegant though) and stands about 120 cm high.
I think both these trees have something to offer as bonsai and I hope others will also be bold enough to add a few tall thin bonsai to their collections.