Simply put, no person may add content to a proposal that is not directly related to the original proposal. You want to add a rider to an HHS funding bill to also fund your pet project? Too bad. You want to include language in a standard farm bill about the second amendment? Not gonna happen.
Under these rules, proposals/bills are forced into MUCH smaller packages and the ability of any particular legislator to sneak in lobbied language becomes stymied.
Congress does not have these simple rules in place. We should force them to adopt the relevant section(s) of Robert's Rules of Order.
Elect enough people willing to self-regulate and pass those bills. The current climate with lobbying money won't ever pass something like that.
As long as a human or group of humans is capable of removing choices for others, there is will be no possible idea of how to prevent the abuse.
Our system is definitely broken, but I have no idea what type of changes might prevent these abuses