To start with, I do have a problem with 'the very last word a victim will have heard, out of all the words in the dictionary, is more likely to have been “tranny” than any other' and it is not just the very obvious point that most trans people who are murdered are not murdered in the English-speaking world. As I know from my own experience, the people who are violent towards us are as liable to just call us 'queer' or 'pervert' as to acknowledge the specifics of our identity.
There's also the issue that honouring all of our dead should not mean erasing the difference between the experience of a middle-class first world trans woman and a young trans kid on the alleys of the barrio in Rio. We have a lot in common - crucial things - but the things that make it more likely that we will not be killed and she might well be are not all those things.
Similarly, I am not sure how useful it is - though I've been known to do it myself - to draw on the oppression of other groups to describe our oppression. It can look a bit like the toxic interface between privilege and appropriation and lead to people not taking our oppression nearly seriously enough.
What I want to say about the T word is this. The period of my life during which I had really bad experiences at the start of transition was one in which I hardly ever heard it. Certainly the men who raped me, beat me up and drove me out of my then home were not using it. (Sorry if that makes me sound like one of the three Yorkshire trans people who transitioned in a sack in a matchbox and considered ourselves lucky...)
Where I did come across it was in 1978 from a group of visiting Australian performers who used it among themselves partly to be loud and proud and partly to create a level playing field of solidarity in which no one got to be more authentic. I rather liked that about it, back then.
It got out into the lgb mainstream and then out into the world. I remember during Toiletgate the security guards who were trying to stop us using gender-appropriate toilets using it to reassure me that they were applying the rules, not being transphobic - as in 'some of my best friends are'. I remember the young LGBT liaison officer who was backing them up, entirely incorrectly, about the law being very po-faced about telling them off for it.
And if only we get to use it, what -as you point out - about our friends, our lovers and our families?
When all this blew up last year, I was persuaded to accept the view of a lot of urban trans activists that we should try and be rid of it. After My Transexual Summer, and the use of it by the Seven, I don't think that policy is viable.
We need to go back to Plan B and reclaim it, and make it loud and proud and a term of solidarity. Thugs and bigots may use it - we just have to use it louder.
I still have gay friends who dislike Queer because of their past experiences, but most of them have had to learn just to suck it up. It is too useful not to reclaim and yet thugs and bigots still use it. And Tranny is our Q word, not our N word.
That is what I think anyway - but we do need a respectful dialogue.