I couldn't agree more. Both should become states (though I personally prefer to integrate DC into either Virginia or Maryland).
It would have to be Maryland, as the land DC occupies now was all part of Maryland. Virginia got its land back in the 1800s. However, Maryland would have to agree to this, and they never would. Adding DC to the state would turn the state power structure on its head, let alone the other effects.
On the other hand, MD would never have a Republican Governor again and would end up with a legislature as perpetually Democratic as Massachusetts.
Indeed. The D.C. has bigger population than Wyoming, yet doesn't have the same rights. I may be exxadurating, but it always seemed to me a bit colonial: direct federal rule and very limited, even now, self-government. The people of the District wants the statehood and should get one. If Brazilian Federal District and Australian Federal Territory have the same rights as other states, then there is simply no rationale, other than petty partisan considerations, to deny it to the D.C.
If Puerto Rico wants statehood (and at one point they voted to remain a "commonwealth") they should get one as well.
Arguably the biggest roadblock is partisan effects. Republicans know DC would just give Democrats 2 Senators that would be invincible to a GE challenge, same with the House Rep. Puerto Rico would probably be pretty Democratic itself, given the current shape of the GOP. The Republican Senate majority has not been above 55 in almost a century iirc, so imagine if Democrats got 4 extremely reliable Senators added permanently? Republicans probably wouldn't get more than 50 - 51 Senators at any one time for the next generation, and might even get locked out entirely for several cycles at a time.
On the upside, Democrats could turn both these places into states if they ever had unified control of the federal government. All it takes a regular bill to begin the process. For DC, the federal district would need to be pared back to only the land around critical federal buildings (Capitol/White House/etc), then the rest becomes New Columbia. Hopefully Democrats will finally fight back on this, because I think if the situation was reversed, Republicans would have attempted to long ago just to beef up their majorities. Hell, they've done worse for this purpose since 2010. I don't care if Democrats do it for purely partisan purposes, as long as they do it. As a former resident of DC, I have always deeply resented this bs.