For me, I will consider myself fully transitioned when I am out at work and dressing full time. I don't know when that will be, maybe 6 months, maybe a year, maybe more or less, who knows! I can't be full time though without a proper wardrobe at the very least. Longer hair, improved voice maybe, maybe not, and at least a reasonable smattering of physical femininity.
My journey will not be over though, probably never. I still want to get SRS and someday fit into a sexy bikini, but all women desire to improve themselves in some way, and I don't presume to be any different. I just want to be seen on the outside for the woman I feel like on the inside. That will be when I have "transitioned".