Our district's member of the Board of Supervisors has referred to the Beltway between Springfield and the Wilson Bridge split into local/thru lanes as the "forgotten segment." He rather strongly indicated at our HOA's most recent annual meeting that no work on there is in the cards in the near term. Perhaps Maryland's project, if it actually happens, will be the event that pushes Virginia to do something along there.
It'd be nice if a reconstruction would include a rebuild for the Van Dorn interchange, which is failing due to an inadequate offramp layout that's essentially unchanged since it was built in the 1960s (the one change was an additional onramp from northbound Van Dorn to the Outer Loop).
BTW, regarding rail transit across the bridge, I read somewhere, but I don't remember where, that WMATA was very skeptical of the concept because of the drawbridge. Seems to me that ought to be the least of WMATA's concerns, but setting that aside, I certainly think their priority ought to be getting what they have operating properly before they expand further (aside from the Silver Line extension, of course), so they shouldn't be considering subway service over the bridge. At one point, DC was supposedly exploring the very ambitious concept of a streetcar line from the Anacostia Metro stop to National Harbor. If they could do that (which I doubt!), and if they could get Virginia to cooperate (which I also doubt), it'd be a nice idea to extend the line over the bridge to connect to the Yellow Line at Huntington or Eisenhower Avenue. I highly doubt any of that has any chance of ever happening.