I was playing around this morning, seeing how much time it would take to use mzitalia.com to come up with high quality baseball players - to see if the effort was worth the time. The 5 players below took me about an hour - but that included figuring out all steps, creating the jersey, and making all the initial decisions. If I were to recreate them now, it would probably take 25-30 minutes.
Once set up then, about 10 players could be created per hour, or about 100 in a full day of work. That's about 2.5 teams (40 man rosters). Let's assume only 2 teams - thus a full MLB set could be created in 18 days of work.
Bottom line, a lot of work even under the best of circumstances.
But for what it's worth, here's what can be done (if you forget about the caps!).