In my opinion the best at returning are the retired players who weren't big names. I think they feel honored when fans send them stuff. That's how igot a lot of my lesser known guys from the 1995 world series Braves team, like Lemke, Avery, Belliard,etc.
As far as cards go I usually send my favorite set. The glossy can smear though so be careful.
As far as cards go I usually send my favorite set. The glossy can smear though so be careful.