Tutoring is extremely common in high-level MTG, whether its Modern or Commander
"Come on, we've got to get this stuff over to Ziatora," she growled as you emptied the contents of the safe
If you want to enter any tournaments, those will also have an entry fee associated with them
The Lander tokens also allow you to dip into a third color, though I expect red-green to skew more aggressive than green-blue
The biggest issue with other cards that provide additional draw effects for your opponents is that the player to your left, the player whose turn other additional draw effects would help first, has access to the extra cards first, giving them an advantage over your other opponents
In most cases, Id say the internet is where its at simply because it has the largest pool of buyers