It’s REALLY difficult to have top 6 and top 4 D upside in the NHL. Foudy is also looking at middle six at best, Helleson bottom pairing. Behrens maybe more but he needs to play NCAA first let alone AHL.
I was personally more impressed with the flashes I saw from Foudy in the AHL versus Ranta. I thought Foudy showed better poise and vision mixed in with a more smooth transition game. On top of this, I think the potential for Foudy to become a center adds additional value. I get that Ranta might be closer to getting games, but he’s also 2 years older. The games Ranta played in, in playoffs I thought he looked blatantly bland if not bad in, so I don’t know if that adds much to the argument for Ranta.
Now in terms of Helleson, I believe you have a pessimistic view of him if you see him maxing out as a bottom pairing guy. If you took the same view for Ranta I think he’s not an NHL player as his IQ may not allow him to make the jump his physical attributes suggest he should. If he’s unable to PK/play solid defense you would need an offensively driven fourth line to place him on and even then it is yet to be seen if he can produce at the NHL level.
Ultimately, I believe all three prospects are within the same tier and it’s a toss up as to who will end up better.