Don't rule out sunflowers. Mine are a bit of a mess right now ... but in this shot, there are 4 types. The Mammoth's are in the back (up to 10-12'). and in the front there are multi-heads.
Lot of birds, lots of bees, pretty decent privacy. At the end of the season, you simply need to remember to harvest one head of each (put them in a paper bag with some rice) and you'll always have more.
The downside is ... when they get a little more mature ... the neighbours come over and start taking selfies.
NOTE: The reason they are a mess this year is that most of them were planted by the squirrels. I usually plant them in a nice straight line. This year, I thought I'd see what nature provided ....
They look magic though. I have some but only a handful and not in a big batch. There do look good when there is a big clump of them together. I think I will go for that next year!