Engine sputtering at about 65

Timing is not causing the stalling in traffic.... it will run fine if all else is good. The extra timing is just masking something else going on. Check your idle timing once the engine is hot, to make sure it is staying consistently where you set it.

Have your vacuum levels come back up to around 20"? Are the float levels set so that the fuel is just at the bottom of the sight plugs in the bowls?