To respond to your first point, I joined Happy Jack in S4. The first three seasons were full of horrible, horrible deals. Deals that should have been vetoed for the good of the league. Because they weren't, the world was full of haves and have nots. After much noise and conflict, the world has leveled off. Personally, I think HJ is a lesson in how to "save" a world. Had we continued down their S1-S3 path, I think we'd be one of those "Only need 11 to start!" worlds.
I started a thread long ago about trading. They may or may not be equal but they have to benefit both teams. Making an offer that doesn't help the other guy in any way is an insult to his intelligence. I'm open to all trades if I receive value. I dealt prospects in S7 of HJ because I felt I could contend. Prior to that, I was building so I was acquiring players who had upside. I always try to figure out what would benefit my trade partner. If he has 7 quality 1B, it makes no sense for me to offer hiim another. Most offers are preceded by a trade chat and/or a check of trade needs. I also see who he has on the block because, if he's trying to trade 3 2B, he's not seeking another. I often think I "lose" the deal in overall value but I'm content if I get what I'm seeking.
I'm usually in contention so I sometimes make a prospect for aging vet deal. My hope is the vet puts me over the top for a playoff spot. I've made a couple that didn't. Those are the worst because I lost part of my future for a failed playoff run.