BAD BOY, GET DOWN!
I would tread very carefully, rack mount points and possibly along that area, you do of course run the risk of denting anywhere you walk.
Be real careful where you stand, especially behind the sunroof opening, it seems to flex there quite easily..
I have climbed all over the roof of my 100.. and as mentioned, it is much stronger near the outer edges. Oh, the area just above the windshield (windscreen) was quite prone to flexing too, but luckily it would pop back out after I stepped off of it
Now that I have an African Outback roof rack on top, I can JOG around the roof if I want