Ooh, good refs! I don't have much to add to the bark, but I'm not at my computer and can do a few edits to show what I'm talking about! I actually wound up using the left one as reference while doing this, what I did was move the bulk foliage down some, smooth out some of the top tufts, then inserted some thick branches.
There's still a bit of an issue with it drawing too much towards the top that I couldn't really fix, but hopefully this gives you some ideas!
EDIT: as always, inspiration strikes right as I run out of time and immediately after posting. I think it might help to break up the top parts into separate groups, sothe branching is more clear!