I've personally always hated mine, and wanted them gone ever since the damned things started growing beyond childhood proportions in the first place. I still hate them, but at least I don't have to worry about spontaneous erections anymore thanks to HRT. I HATE, HATE, HATE those.
Even if I wasn't transitioning, I'd still want them gone. Which is actually why I was a member of the Eunuch Archive in the first place... because there was indeed a very long time where I wasn't allowing myself to embrace my trans thoughts, but because my physical dysphoria with my "lower" body was still so strong, I fantasized about being nullified instead.
With that said, though, no. There is absolutely no requirement that you dislike your lower parts in order to be transsexual. Many don't mind them whatsoever, many don't want to go through the hassle of surgery, many don't feel like it's important enough, many are afraid of regrets, and all of those are perfectly fine. Having a vagina or a penis is not what makes you a woman or a man. And hell, there are even some men who are not transsexual in the least, but still do feel this lower dysphoria and want to be castrated/penectomized. Even some who want a vagina but to remain presenting as male, because they are not transsexual. (The "mangina" man. Yes, he does exist.) One's physical body and one's gender identity are two completely independent variables, and all are spread across a very wide spectrum.