We should have 19 Supreme Court justices

The Constitution says nothing about the number of Supreme Court justices we should have, and in American history the number has varied from five to nine. But in other countries there are as many as 140+, and the average number is 19.

Yes, yes, I know FDR tried to pack the court to change its political complexion. I'm not talking about that or anything like that.

What I am talking about is the third branch of government being surmounted by too few people, and given the slow oscillation of legislative control between the two major parties, many important issues are decided by one tie-breaker like Justice Sandra Day O'Connor or Justice Kennedy--and now Chief Justice Roberts--while most of the rest reliably vote one way or another on politically divisive issues.

There are 13 circuit courts. At the very least we should have one Supreme Court justice for each of these. 

Apart from that any number is pretty arbitrary. I think 19--has to be an odd number of course--would be big enough to ensure greater diversity of opinion and source of nomination. Add a term limit--say, 25 years, to lean on the generous side--and you wouldn't wind up with one person deciding major policy issues' constitutionality in case after case.

As for court packing, you could have five of the additional 10 nominated by the President, the other five nominated by the leadership of the other party. So the current political complexion of the Court would not be changed. If not that, surely both sides could agree on a way to get up to the 19 number that didn't tilt the playing field in a way that was substantially different than it is now.

I want that because it's critical that the American people believe in the legitimacy of the Court. And I believe having 19 justices instead of 9 would make the Court seem less idiosyncratic and less dependent on a handful of swing justices, and thus seem more legitimate.