well i can say both my characters on bt have 70 odd prestige ratings.
one of them (yuri, p/d lord) has...
reputation 25
p 77
h 49
notoriety/deeds/skill - blank
legacy 24
ruler/duke - blank
lord 63
knight 31
everything else blank.
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the w/h knight
rep 24
p 72
h 49
legacy 10
knight 38
rest blank.
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the knight has bigger estate than the lord. so perhaps it's to do with number of peasants under his estate? (he's definitely not been on island longer than the lord... realm time would be same, given realm flip at the same time)
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and funny enough.. both of them have high prestige. the priest got some of the prestige from investing loads XD