At 8.4 hit (rumors have it that it went up to 9 now) you wont miss on a 73.
At 490 def you wont be crit by 73.
Going past 490 def you will still be getting dodge, parry, block, and chance to be missed. So it is still a VERY powerful stat even past 490.
Seeing that you are just about to hit 70 i wouldnt shoot for a ton of hit since it will hurt the rest of your stats. Keep in mind that down the line when you want to start tanking more advanced content, hit will be a must!
At first cover your 490 def, then try to get your stam up. Then eventualy make your way towards the Avoidance, Block Value, and Hit gear.