Door Frame Dilemma

I was all excited last night for a trip to Home Depot to get sheetrock and related supplies, and some 1"x4"s in anticipation of starting the installation of the new door frame trim in my bedroom.  Red came over and we stood in front of the trimless door frame to conjure up a plan.  Hmmm.

We concluded that when the trim and sheetrock was originally installed (we shall not guess what year that was...) that the trim was installed first, and then they sheetrocked around it.  Having done it that way means that the sheetrock butts up against the edge of the trim, as opposed to the trim laying on top of the sheetrock.

This photo shows that the trim was 3.5" inches wide -- precisely the gap left between the door jamp and the edge of the sheetrock. (The measure shows 4, but you can see that my tape wasn't flush against the jamb on the left.)

I want the trim to go on top of the sheetrock so that I get a cleaner look.  My plan was to add a vertical strip of sheetrock and then affix the trim on top of that.  But when I do that, the sheetrock bumps my trim out away from the jamb and gives me a gap.  Here I am holding a scrap piece of 1"x 6" up along the door for illustration (my finished trim will not be that wide.)

And, the resulting gap on the side

We talked about moving the door jamb over/out to match the sheetrock, but that only leaves me with the same issue on the other side of the door. 

Also complicating things is that I was going to use 1"x4"s for the trim -- which in reality would give me the 3.5" trim.  But that isn't wide enough to cover up the would-be new sheetrock seam; the seam would be right next to the edge of the trim.  Does that matter?  Maybe not.  Is it optimal?  Definitely not.  So I may have to rip 1"x6" into 4" trim and have my trim a bit wider than I wanted.  (My baseboards are 6" but I think that would look too heavy around doors.)

Then Red suggested since I'll be ripping the boards anyway, to rip a narrow piece to insert behind the trim to fill the gap.  Here I am holding a random block of wood up to illustrate (obviously the final product would be the same stain... ahem.)

Yes, for a while it will be natural wood trim against a painted door jamb; not the most asethetically pleasing scenario, but hey it's a work in progress.  I don't know how to build new doors and jambs yet... although perhaps I should tackle all that now... hmmm.

We also talked through whether or not pulling down all the sheetrock on that wall and re-sheetrocking it would solve the problem, but it doesn't seem to.  When we arrive at the door frame, we're in the same situation.

We also talked about re-building the door jamb, and using a 1"x 8" rather a 1"x 6"... or possibly ripping it down so that it's 1" x 7" -- but then I'm back to doing the door jambs and doors before I am really ready for all that. 

Do all doors (pun intended) lead to just a total door trim, door jamb and new door project on a doorway by doorway basis vs. doing the trim now and the jambs and new doors later?  Inquiring minds want to know.