The patches to the constitution aren't as deeply thought out as the original one. The Senate wasn't even an elected institution until 100 years ago, whether that is better or worse than an appointed system is mostly a false dilemma as there are more than two options. Pointing out that our constitution isn't really geared for the current process is a first step of getting more inspiration on how it could function.

When you patch one aspect it throws the other aspects out of whack.

"Basis of land"? LOL. Are you referring to the 50 individual state governments that make up the United States of America? Most Europeans don't know this, but the first government in the world to ban slavery was the U.S (Vermont). The US isn't one homogeneous zone. There are 50 individual governments that write their own legislation, have their own taxation systems and have military's (state guards). California is free to create their abortion access legislation as is Texas. Many states in the US legalized Weed despite the fact that the federal government has some bizarre policy in place (which isn't constitutional).

I hate to burst your bubble but Pope Zachary ended slavery in Rome in the 740s, banning the slave trade and manumitting all slaves already present by purchase of the church & state.

I think they were making a jab at the Electoral College system in USA.