If defense is truly what your looking for, then WCS is your guy. He is the best defensive player in the entire draft. As or Winslow, if he was an inch and a half taller, I'd be all over him. But he was 6'4.5" in his bare feet. And through some miracle, somehow he found shoes that added two inches to his height, making him 6'6.5". Which is borderline tall enough to play the SF position. I had Winslow and Stanley Johnson dead even on my list all year long, and I still do. I realize that Winslow shot the ball well in the tournament, but so did some kid named Derrick Williams and he was actually legit size. Don't get me wrong, I think Winslow will be a good NBA player, but nothing is guaranteed just because we wish it so.
To say that we don't need offensive players is just as ridiculous as saying we don't need defensive players. What we need are complete basketball players that can play both ends of the court. This isn't a war between defense and offense. It's not an either or. It's not as though you can't have both.
When I say we don't need offensive players, I mean those whose calling card is offense. I actually listed several attributes on that side of the court for both Kawhi and Iggy, and said that I see some of the same in Winslow. Specifically, I mentioned ability to spread the floor, finishing well around the rim, and not needing the ball to be effective. If you read my post in full, I'm not suggesting that we need players who don't play offense. Quite the opposite in fact. Just that, that should not be the primary focus.
While everyone loves guys who are great defensive players, if they are bad offensively, they can really hurt their team, as teams can leave him to double team. This is the reason that while I love Tony Allen, I feel that Bowen helped his team a little bit more, since he helped spread the floor, and you couldn't cheat off of him on the three point line. This is the same reason Leonard and Iggy are so valuable.
As for Winslow, I understand the concern. However, I think we refuse to accept that the league has been getting smaller and quicker (probably we are reluctant to admit it), and Winslow can play SF in the NBA. How many SFs in the West can easily shoot over him? Plus, he is strong enough to prevent most of them from establishing good post position, or muscle him down.
Perhaps some of the other candidates that might be available are better than him. I don't watch even a fraction of college BB as you do, so maybe I'm wrong. However, based on what I've seen, I hope we pick him, instead of trading down, picking some other guy, and see Winslow become a star somewhere else. Maybe I'm giving too much credit to a guy who is not even in the NBA yet. However, I think the kid has a chance to be really really good, and I hope he does that in a Kings jersey.