You know what I would do with I-95 in the Philly area ? I would put I-95E on the NJ Turnpike and I-95W on the current I-95 through Philly , finally build the interchange on I-276, then use the remainder of I-276 east to rejoin 95 E & W. It's too bad noone thought of that before.
I would go a bit further (yes, this post would more, fall in the fictional highways category):
Have the NJ Turnpike south of Exit 6, The Delaware Memorial Bridge and the Delaware stretch of I-295 be designated as I-95E (E could stand for either 'East' or 'Express').
Leave I-95 through PA and NJ in its ultimate/final layout (post-PA Turnpike Connection) but move the Wilmington, DE stretch of I-95 onto the current I-495.
Have the Wilmington stretch of I-95 designated as I-95W (W could stand for either 'West' or 'Wilmington').
One could argue that the above could be allowed because BOTH offset routes (E & W) begin and end with the parent route. IIRC, every former suffixed interstate, except the two I-35s in MN & TX, did not start and end w/the same route.