Stimbo wrote:

What are the recommended procedures in obtaining an IFR clearance
enroute?

Flying from NJ to FL, I prefer to fly VFR, but undoubtedly I will
encounter IMC along the way. If I filed IFR in advance, it takes 1/2
hour or more to clear it through ATC. I obviously cannot wait 1/2
hour if I encounter IMC enroute.

If you don't have a pretty good idea of where you are likely to encounter
IMC en route, you haven't done a very good job of flight planning. If you
have, then a composite flight plan works quite well.