Some experiments and trees!
Starting with a VERY good modular-tree plugin for blender and building up from them, i managed to create some interestingly shaped trees.
A LOT of work is involved after the scripts generates a basic shape, but still it's a great starting point.
The very first iteration wasn't much interesting, but after a few tries i got to a better level:


Painted, with a bit of Woodland Scenic, they do their job well.


And with the help of some hacky friend I modified the script for my purposes, and another whole lot of work, I had better and even more detailed trees!

Now I have to play with the parameters to generate more interesting shapes, then start to manually detail all of them again. Wish me luck!
Cheers
Jack