Logan Austin and Aaron Young have four place names between them, and now they both head to new clubs in a busy trade period for Port. St Kilda acquire the fringe Canberran defender Austin while sometime best-22 small forward Aaron Young heads to the Suns. Both go for late future picks.
Of the two, Young protects to have a better year in 2018 and be more valuable overall due to a bit better track record. However, Port have gotten more in return for Austin: 
We’re not 100% sure which 4th round future pick Port traded here, since they also held Adelaide’s as a result of the Young deal. Port get back a worse pick from the Saints, and the difference in expected yields isn’t too far off Austin’s projection as a bloke who mostly played reserves this year and got half a season last year. Austin is a young tall, and sometimes they develop late. It is clear that this is the bet that the Saints have made on Austin.
For young, Port get back the Crows’ 4th rounder from the Suns, which we suppose gives them an extra incentive to death-ride their cross-town rivals next year.
A late 4th round pick is expected to produce about half of what Young will from here.
Why did Young go for less? We’d speculate that Port were keener to see him off for salary cap reasons than the draftee-contracted Logan Austin. Or it could just be as simple as how the negotiations played out over what are, ultimately, some pretty low stakes picks.
Verdict: Austin trade fair, Young trade likely a big Suns win
Note: This post is part of a series of posts using a valuation method called Player Approximate Value (PAV) to evaluate trades for fairness and balance. Elsewhere, you can read much more about the method and theory behind PAV and also about PAPLEY, the projection method used to derive expected future PAVs. This method expresses both picks and players in terms of expected future value allowing them to be compared on this common basis.