Gollum-Isildur: I also see a discrepancy of about 500 years, where Gollum owned the Ring himself. I forget how long Isildur had it, but it was an insignificant amount of time compared to Gollum, who only died after losing it, then gaining it back. (Details, details..)
And btw,
Eve... I wonder if PJ's decision to have Isildur killed by arrows linked in any way to Boromir's death by Uruk arrows?