Firstly, apologies, I was upstairs on the phone for a good while
A very interesting map and one I admit that raises many of those historical questions one knows bugger all about beforehand.
But, it we take the treaty line of 1819 to be established fact, then we're looking West of it to be Mexican or Texan. If you want to delineate, take this area then the bits which are in OTL Colorado, Wyoming, Utah, Nevada, Northern Arizona and North-West New Mexico would equate to Deseret. Texas as an independent state is West of the 1819 line, the pink area inclusive of that in OTL New Mexico. The remnant of the green area of Southern Arizona and South-Western New Mexico forms the ATL state of Nuevo Mexico. California is Upper California in Mexico (as opposed to Lower or Baja California)
Looking at the states which are part of the Union in the 1870s then you're right, we need to do something with Wyoming and rump Colorado. However, given that they are contiguous to the Indian Territory (Oklahoma to be) they may not become organised in this period anyway.
By the same token, for the new states ignore Oklahoma which will remain Indian Territory for now, but look at the Confederacy as including OTL CSA states plus Kentucky, Maryland and there being no West Virginia in this ATL
My main difficulty with maps is blending them all in one. For example in the one I posted, its quit6e obvious and clear where Vandalia, Transylvania, West Florida and East Florida would be, but by the time we get to this map how am I to transfer that to here ???
How am I to identify the rump Francophone area to become Acadia (Northern Louisiana/Southern Arkansas ?), and how to identify the Yazoo area mentioned as well ?
As for the new new state names - take Franklin to be anywhere in the North of this area that has not been reassigned, and Jefferson anywhere in the South.
For Monroe take all of Maryland, peninsular Virginia and Northern Virginia not part of the old federal area (which was later reduced in size)
For Jackson take Georgia minus whatever is lost to East Florida, and plus whatever slither of land ios left between the named areas (eg Transylvania) and OTL Georgia
This should leave a rump Virginia to be Roanoke, and the Carolinas to be split in three along river boundaries
Grey Wolf