The one handed buckler shield should be an AC +1. It also should be a shield you can use as a reaction if you aren't armed with it and using a single handed weapon. This will allow players to use long swords two handed and encourage it. Most players will still choose to use a greatsword or long sword and standard shield.
Then there is the buckler shield that straps to the forearm or is part of the gauntlet. This one allows players to still use a greatsword, maul, spear, polearm, or any other two handed weapon. This one will be an AC +1 shield but it will also be a -1 to hit using two handed weapons. The reason for this is because without the -1 to hit everyone who uses a two handed weapon would want a buckler shield. With this rule I would even entertain the idea of a character having two of these for a AC +2 and a -2 to hit.
I hope to start testing these out in future games ran in the Tabletop RPG One Shot group on Facebook. What do you think of these potential home brewed items or rules? Are they over powered? Do you think they are balanced enough? If you end up using them in your future games please share your results and opinions of them.
Here on my blog there will be more home brewed things like this so continue to check back for more.