Let me start off by saying this is incredibly america centric, I genuinely don't know how applicable this model could be to other countries without similar circumstances to the US.

cracks knuckles

On the executive:

• Abolish it entirely, the independent executive has been demonstrated as a parasitic leach upon the authority and responsibilities of the representatives on the people. Replace it by dividing the responsibilities of state to the senate and responsibilities of government to the house. Just because America has a serious Roman Republic fetish, the official titles of the House Speaker and Senate Majority Leader will be changed to Consul and Tribune respectively. One leads, the other checks.

On the legislature:

• House now assigns one member to a state for every 50k residents tallied in the census, and the house assigns the Senate 27 seats for states, 21 for territories and recognized indigenous nations with 1,000 members or more, and 15 for labor unions with 5,000 members or more. Multiples of 3 so that the rotating terms don't result in elections where some people don't get any say in the senate.

• House terms now 4 years and senate terms now 4 year rotating terms of 12 years.

• House districts sized between 5 and 9 seats per optimized for compactness and the ability of the residents within to easily understand where their polling place is and who they're voting for.

• Senate seats voted on together in a batch. Same for each district's reps.

• Style of election is multiseat STAR to make sure each delegation is a rough estimate cross section of that region's political sentiments and what everyone feels is a fair representation of such.

• House and Senate officer positions are likewise elected via multi-seat STAR save for 2nd-9th place seats being able to attend the meetings but not having the right to author orders from the office.

• House and Senate get to veto eachother's specific actions but it has to be by a minimum of the same margin the action was passed by, and no filibustering of any kind, that's just spoilsport behavior.

• House passes laws and other such schtuffs, Senate issues pardons and other such schtuffs.

On the judiciary:

• Broadly, every "SCOTUS" case gets it's own randomly assigned panel of judges to block jurisdiction shopping bullshit. The chief justice is the seniormost of the selected judges and acts as foreman.

• There's rounds of appeals, including a penultimate one where all the judges who've heard the case come back all at once for an "en banc" trial of the case, but ultimately a "Synod" can be convened for a big enough question where literally every federal judge is summoned to basically get a 2/3rds consensus on any sort of ruling on the issue at hand.

• Judges serve 12 year terms renewed by the Senate if no ethical or constitutional misconduct is identified.

On Federalism:

• Felony Law is the exclusive domain of the federal government.

• Criminal Law is shared with Federal Primacy.

• Civil Law is shared with Local primacy provided it doesn't violate constitutional rights or isn't a federal domain in which, federal primacy again.

• If a law is overridden or ruled unconstitutional, it's not just put on the shelf, it's stricken, it's gone for good and can't come back unless it's re-passed post it being deemed constitutional again.

• States also get overridden by Indigenous Sovereignties on civil law, and where criminal law and jurisdiction is in conflict, the dispute is settled by the feds.

• Special carveouts for Hawaii, Alaska, the territories, and Indigenous Sovereignties.

On the continental 48:

• Reorganized by Watershed:

• • California, California Watershed
• • Sierra, Colorado and Great Basin Watersheds
• • Cascadia, PNW Watershed
• • Heartland, Missouri and Arkansas Watersheds
• • Norteña, Gulf and Rio-Grande Watersheds
• • Sherman, Lower Mississippi, Tennessee, and Southeast Watersheds
• • Ohiagan, Great Lakes, Ohio, Upper Mississippi, and Sourris-Red Watersheds
• • Longhouse, Midatlantic and New England Watersheds

On Public Services:

• Hire Estonia's tech people to beef up America's public service provisions, see Kraut's vid on what their system is capable of but basically it would save America billions annually just in costs of providing services and bureaucracy costs.

• Federal standard setter market participant orgs to keep critical industry participants sharp.