You make some valid points @elantaura . Long term relationships could be awarded by increasing the anniversary benefits each year. Perhaps the longer you are with a player the more bound items you can trade. Or the greater the grouping benefits.
The Progeny concept would require Progeny slots, so you wouldn't have to bench anyone to add a child character to your lineup.
What ESO really needs is an Auction Horse.
That's right... Horse.
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