I read your post with great interest. We have been doing extensive research for about four years, and although we'd rather put this all behind us, our children are now asking a lot of questions, so the "search" goes on. I spent all of last evening comparing all of your references in the Kingdom Interlinear (KIT), which the NWT uses; the Emphatic Diaglott, and the Hebrew-Greek-English Interlinear by Jay P. Green. All three are different in a number of instances, and I will follow with a few in just a moment. The KIT, according to the forward, is drawn from Westcott and Hort of 1881. The Emphatic Diaglott is from the Vatican 1209. I found the Westcott and Hort interlinear online at "Online Greek Interlinear", which may be of use to you. I did find that when there was a "deletion", it was because the original manuscripts usually did not have that text, and most modern translations also delete them. The following is what I found on some of your references.
John 1:1= WH says "god was the word", as does the KIT, although in the english translation, it adds "a god". It's interesting, in the forward of the KIT, it acknowledges the Greek had no "a" or "an", but would be added at the translators discresion.
John 8:58= WH reads "I am", just like the KJV.
Rom 14:10= WH says "of the God". ED says the "seat of the anointed".
1 Tim 3:16= WH says "God was manifest in the flesh".
Rev 5:14= WH adds "lives forever and ever" in the English translation, but in the literal Greek, it ends as does the KIT.
Acts 7:59,60= WH reads nearly the same as the KJV.
1 Cor 10:9= WH reads like the KJV.
1 John 3:16= WH reads like the KJV, but has [of God] bracketed.
Col 2:9= WH says it is "dwelling entire the complement of the diety bodily".
2 Tim 2:19= WH reads like the KJV.
Col 1:16= WH reads like the KJV.
John 1:3= WH reads like the KJV.
Acts 2:30= WH reads like the KJV.
Rom 8:34= WH reads like the KJV.
2 Cor 13:14= WH reads like the KJV.
Mt 24:36= WH reads like the KJV.
I was surprised by many of the differences between the KIT, ED, and our Hebrew-Greek-English Interlinear, but was shocked when I read from Westcott and Hort. It was different from the KIT (NWT), even though the KIT says "the main material will be found the original koine Greek text as revised (in 1881 C.E.) by the renowned Greek scholars B.F.Westcott and F.J.A. Hort". My research has shown the NWT to be dishonest in many scriptures, adding many words or changes, without any [brackets].
Thank you for your research. Your work is appreciated.
Little Bo Peep