In re: "Manageable" states- There is an informative book out called, "How the States Got Their Shapes" (forget the name of the author), which among other things, notes that Th.Jefferson recommended that new states not be more than about 4 degrees of latitude and 6 degrees in longitude, (think !8th-early 19th century transportation) such that government would be physically closer to the people and one state would not dominate the Union. Other than Texas, California, and Montana, the Midwest and the Prairies/Mountain West mostly fit this (Minnesota might be one exception).
More salient to me in this discussion is the increasing lack of comity and the tribal partisanship that poisons the well of democratic (note small "d") government. The U.S. Constitution is famously called "The Bundle of Compromises"
As an aside,I think Tim Draper hasn't gotten the memo that this is old and really tired news in CA. Dr. Z is correct, this goes back under American rule to at least 1854 (slavery and all that, don't ya know), and was a pronounced thorn in the side of the Mexican governance of Alta California before that.
Setting aside some issues, where would places like Glenn, Plumas, Lassen, Alpine and Tehama counties find sufficient tax revenues for their bits, with extraction/resource industries on the decline? Just like the red State/ blue State divide, the Democratic strongholds in the urban/ coastal areas are the net subsidizers of the Republican hinterlands. You could look it up. And this ain't anything new. There's a lot to be said for strength from diversity and playing well with others. Lastly and besides the point; How is it that red as a color is now associated with conservative/Republican ideology and blue with liberal/Democratic? That's just plain bass-ackwards to the conception of the rest of the world. Oh, wait... It's American exceptionalism (Another concept we could well do without. Were all just people, and some of us like trains!