I've read all the thread and I confess that now I'm pretty much torn between the ISTJ and INFP. It would be safe to say that you're a very balanced individual and that you can work with all your functions very well. Congratulations
I'll try adding some arguments supporting my INFP theory later (I indeed have some ), but I think ISTJ is possible as well.
As a matter of fact, I absolutely hate the MBTI stereotyping, especially the S/N stereotyping, and I'm sure I'd agree with your thoughts on the S/N difference. Actually, I understand the S/N difference very well and I really don't need any further explanations. (I may have worded it wrongly, but be sure I know it's not about liking theories - it's about how one actually ends up constructing their theories.) To your arguments, Ruthie really doesn't strike me as 'modernized' at all (I wouldn't be surprised if it insulted her ), but anyway, I don't think this is about any modernization or flexibility, it is about underlying structures in one's thinking process. This is really the only thing that the ISTJs I know unfailingly share, and I'm not sure if Ruthie does.
Also, it is true that I haven't exactly interacted with Ruthie here, so I don't know how well she actually uses Ne. Of course, if I knew her in person, I would probably be able to tell readily what type she really is, but here I have to work only with the limited information she gave, and the truth is that either J or S certainly aren't written all over them.