I wouldn't even consider jumping in the old city. there are a lot of building in TelAviv and Haifa you might get lucky with. be aware of the strange wires above most streets. I went out to the Negev and found a bunch of nice cliffs. there is actually a nice platform out there to static line if you like low and gnarly. if you do decide to jump in the Negev, do it early in the morning. the sun will beat you down, im a florida guy who is used to the sun, and it sucked! pm me if you want some beta on the Negev. i've also heard there are some wingsuitable cliffs near the dead sea. but they are a pretty good hike.
Have been in israel for a week, there is TONS to do around the beaches, Jerusalem might be a bit tough though. Also the Dead Sea was 110 degrees on Saturday when we went, probably should skip those hikes for now!