Thanks for your reply. I'm just putting the idea forward hoping others agree, and maybe help trying. Maybe more and more managers will see the benefit and we can bring forth a shift in strategy. As more managers train these type of players, completing your roster will become easier. It sounds a little like a utopia, but I like out of the box ideas.
I think the bigs are easier/faster to train, because you only need high levels of IS and OD, and then some RB and a little of the other skills. If you can get them to finish training at age 23, you'll be approaching an ideal starting 5 pretty quickly.
About trading the players with partners, what if both put a player on the wire, and bid on eachother's players? As you bid, the other guy gets more cash available allowing him to bid more on yours, so you can do the same. Basically you can big 5 million on eachother's player. I don't think that high a price is desirable for the transfer market and possibly forbidden, but seeing as the players won't fit very well in regular teams, I don't think other managers will want to spend a lot on these players. If you bid at the high part of the market value, I don't think regular managers are gonna outbid you.
And wether it's worth it? I don't know, that depends on what you want. For me, I think it would be worth it to be succesful with my own strategy that no-one else uses. Also, to be the best you gotta have a real good advantage (or real good luck), and having a roster that only costs you 1/3rd to 1/2 of the salary of competitors, I'd say you'd have that kind of advantage. If you want to win it all, you need to put in a lot of work, so if you aim high I think it's worth a shot!