Splitting up California would only prove to weaken the region as a whole. Sure you may gain a couple senators and college votes but theres no guarantee that the resulting states would be economically solvent. You could just end up with a bunch of Mississippi type states, also a good chunk of California is quite conservative.
Combining the Northern states has far clearer advantages both politically and economically. Namely it would allow a better spread of taxes.
Splitting up California, would work too. But really, we need to finish the Interstate Popular Vote Compact.
Splitting up California would only prove to weaken the region as a whole. Sure you may gain a couple senators and college votes but theres no guarantee that the resulting states would be economically solvent. You could just end up with a bunch of Mississippi type states, also a good chunk of California is quite conservative.
Combining the Northern states has far clearer advantages both politically and economically. Namely it would allow a better spread of taxes.