Hello! So since I made the first post, I've gone back and made some changes, additions, and corrections to my work. Now that most of that heavy lifting is done, I'd like to share the (as of now) final result with you guys, as well as the changes and additions that were made! HUGE shoutout to Not_Madigan, TedBessell, HCP, Razze, Technocracy Timmy, and YoungTexan, who all contributed to this project.
First off, I changed the map. The original version looked unsightly in the west, and it is a problem that I fused Mountain West states for being too small yet somehow saw fit to add DC as a separate state, even though it's smaller than most of them. So here's the new map!
First of all, DC is now part of Maryland rather than its own separate state. Second, I took the gigantic hideous Mountain West amalgamation and divided it into two states. The first, Dakota, is simply the twin Dakotas made into one, and is roughly as populous as Maine. The second, Idaho, takes the existing Idaho and adds Wyoming and Montana. It's about as populous as Iowa -- in fact, it being smaller actually gives Iowa a second Senate seat in the 2000 census, but in the 2010 census it leapfrogs Iowa and takes its second Senator.*
To visualize the partisan balance of this map, let's do the same thing we did earlier with the last map. This time, I'm considering a "swing state" as either a state that was within 5 points in 2012 OR 2016, or flipped between those two elections.**
Democratic states: 33
Republican states: 33
Swing states: 30
Yes, I will defend Virginia and Iowa as swing states; the only questionable one here is Maine. But anyway, there is no strong bias in this Senate formation toward either party. The only downside to the change is that, by giving up DC and splitting the Mountain West multitude, we traded one medium and one small state for two new small state, which pushes the threshold for extra senators down. Iowa, which always was limited to one Senator in the old map, gets a second one here until 2010, and Idaho (the smallest state post-2010 to get 2 senators) is barely any bigger. But that's not TOO big a price to pay for a massive aesthetic upgrade and a stronger case that this is an unbiased map.
Take a look at the spreadsheet to see a few Congressional formations under this map! I had to take some liberties with figuring out who would win elections that didn't happen in this universe, but I'll defend all of my choices.
I will admit, in deciding which Senator to cut from the 16 small states, I actually arranged it the way that maximally benefitted the Democratic Party... in 2009. Looking it over, I preserved Ben Nelson, Mark Begich, Jeanne Shaheen and Harry Reid, (though that one was intentional because I wanted to preserve important figures like Senate leaders and future Vice Presidents) but I'm not losing any sleep over it because in 2018, the choices actually matter very little. Republicans get Capito over Manchin, but Democrats get Cortez-Masto and Angus King. If you set aside the fact that I deliberately preserved Nevada Class 3 to protect a Senate leader, then it comes out to a wash.
The spreadsheet also shows two other things. One, what Congress would have looked like in 2005. I wanted to see if the GOP could ever have a majority in this map, and as it turns out, yes! In 2005 they control the Senate, 50 to 46. And second, it shows... some of the effect this has on the electoral college. By eliminating some small states and making others count for less while bolstering the big states, it flips the 2000 election to Al Gore. Not by much; flipping razor-thin Wisconsin restores the status quo, but it's still interesting to look at.***
And now, for the fun part, the part that makes the mods question whether this should be on the What-If board. Once again, this is in two parts. First off, new state names. Dakota and Idaho are pretty straightforward, but I did some name changes for the split Californias. Originally I had SoCal be California and NorCal be Polk, but that didn't feel right. Brainstorming other name ideas, I realized a problem: neither state should be named California because that's the name for the entire whole. Neither should get that title that belongs to the fusion.
So SoCal is now the State of Chaplin, (CH) named for Charlie Chaplin. NorCal is the State of Frémont, (FR) named for the first Republican Presidential nominee ever and named as such because this is the land of Atlasia and I had to.
Secondly, the really fun part. Dakota has to share one Senator for what we know as 2 states. Idaho gets 2 instead of the 6 it usually enjoys, and one of them only came into being after 2010. TX, FL, NY, FR, IL, PA, GA, OH, MI, NC, NJ, WA, VA, MA, and IN all get one extra Senator, PR gets 2, and Chaplin gets 3(!) due to California's two senators both being given to Frémont. So myself, Not_Madigan, TedBessell, HCP, Razze, Technocracy Timmy, and YoungTexan came up with a list of the people we feel would fill those spots.
Just for frame of reference, Class 1 Senators were elected in 2006 and 2012, Class 2 Senators in 2008 and 2014, and Class 3 Senators in 2010 and 2016. So here's the list!
Texas Class 3: George P. Bush, Elected in 2016 (R)
Chaplin Class 1: Before 2018, Susan Davis, Elected in 2000 (D)
- After 2018, Toni Atkins (D) after 2018
Chaplin Class 2: Linda Sanchez, Elected in 2008 (D)
Chaplin Class 3: Kevin de León, Elected in 2016 (D)
Florida Class 2: Adam Putnam, Elected in 2014 (R)
New York Class 2: Gregory Meeks, Elected in 2002 (D)
(Frémont gets the existing CA Senators: Dianne Feinstein in Class 1 and Kamala Harris in Class 3)
Frémont Class 2: Barbara Lee, Elected in 2008 (D)
Pennsylvania Class 2: Joe Hoeffel, Elected in 2002 (D)
Illinois Class 1: Before 2018, Lisa Madigan, Elected in 2006 (D)
- After 2018, Cheri Bustos (D)
Ohio Class 2: Jon Husted, Elected in 2014 (R)
Georgia Class 1: Jack Kingston, Elected in 2012 (R)
Michigan Class 3: Dan Kildee, Elected in 2016 (D)
North Carolina Class 1: Dan Forest, Elected in 2012 (R)
New Jersey Class 3: Frank Pallone, Elected in 1998 (D)
Virginia Class 3: Tom Periello, Elected in 2016 (D)
Washington State Class 2: Dow Constantine, Elected in 2014 (D)
Massachusetts Class 3: Deval Patrick, Elected in 2016 (D)
Indiana Class 2: Todd Rokita, Elected in 2014 (R)
Puerto Rico Class 1: Aníbal Acevedo Vilá, Elected in 2006 (D)
Puerto Rico Class 2: Pedro Pierluisi, Elected in 2008 (D)
Idaho Class 1: John Barrasso, Elected in 2006 (R)
Idaho Class 2: Steve Daines, Appointed in 2011 and Elected in 2011 (R)
Dakota Class 3: John Hoeven, Elected in 2010 (R)
For now, that's all we got! I'd love to hear thoughts, endorsements, questions, nitpicks, etc in the replies. In the what-ifs board, keep a lookout for Senate races from 2006 through 2016 and a 2018 battleground map under this map and distribution.
*Better explain how this works, since it's a little different from the Indiana/Arizona example in the OP. Idaho starts out with a single Class 1 Senator, and Iowa starts out with a Class 2 and Class 3. There's no obvious seat to switch over, so instead whichever seat is up first moves from IA to ID. After the 2010 census, that would be Class 2, as 2014 comes before 2016. With the seat decided, the rest plays out the same as the IN/AZ example in the OP.
**I will now defend Virginia as a swing state. While it wasn't within 5 in 2016, it was fewer than 5 points more Democratic than the nation that year, in addition to being within 5 in 2012. Plus, Tim Kaine was on the ticket. The VP nod typically nets their home state 2 extra points for their ticket. Remove those 2 points from Kaine's influence and HRC only has a 3 point cushion in the state -- less than the 5 point window and only a point to the left of the National Popular Vote.
***Don't worry Trumpists; while this changed EV allocation saves Al Gore, it is not NEARLY enough to save Crooked Hillary. I didn't run the numbers but Trump's EV lead is too big. The only thing it might do is reduce Trump's EV Count to below 300 in the 290s range and narrow the gap such that flipping Florida would have changed the outcome. But no, Trump still wins in 2016 with this allocation.