Dutch, glad to see you taking the plunge. The following is just my take--other platers (and there are certainly some who are more accomplished than I out there) certainly may have different approaches.
I think you have the essential elements identified, but it is not always a linear process. My approach is to first identify the possible plates to which a given example may be assigned. This can be done based on type and/or on relief, often in conjunction. After first ascertaining that the stamp has not been doctored (e.g, perfs trimmed off or design elements drawn in) I look at the relief. Type V reliefs are easy to identify and take you to Plates 5,7,8,9 and 10. Similarly, the reliefs from Plates 11 and 12 can usually be identified at a glance (heavy dot in the medallion oval behind Franklin's head). The three reliefs of Plates 1 (both states), 2 and 3 similarly can usually be identified immediately (Plate 1 Late has the added tip-off of the recut lines). That leaves Plate 4, which is uncommon but which features a unique set of reliefs. Once you have narrowed down to a plate or set of plates, further reference to the reliefs will help you identify which rows on the plate(s) the stamp in question might come from. Then you can look for positional plating marks. There are other clues that can help you narrow down the possible plates up front (guide dot position, color, overall appearance with regard to blurring and mottling etc.) that experience will enable you to use.
The published sources you list are the ones you need. Neinken is an improvement on Ashbrook as far as the plating information goes (Ashbrook delves into areas of postal history that Neinken does not). However, Neinken should be supplemented with updated plating information published in the CHRONICLE. In addition, you should definitely look at the 1c Franklin Plating Archive created and maintained by Richard Doporto (http://www.slingshotvenus.com/Frank...v_Main.html)
ETA: stallzer's post appeared as I was writing this. Definitely agree with him on the use of the Plating Archive.