I am almost certain that I could possibly have another favorite tea had I not started out with and immediately liked sencha.
I mean, ever since, I have been exploring the world of Japanese tea with only a very few exceptions of the occasional Chinese or Indian tea. There is just so much to try and unless you're sharing a lot of your teas it's going to take a long time to explore just one category of tea to a satisfying degree.
What I am trying to say is that for me personally, my favorite tea is not necessarily my favorite tea out of all the teas in the world (since I haven't tried them all) but rather my favorite tea out of all the teas that I've had... so far.
So, there is a possibility that I could enjoy another type of tea more in the future but I don't think it would ever lead me to give up sencha.
I hope to broaden my horizon as far as other types of tea are concerned with some of the upcoming OTTIs here on TeaChat. It's hard to sample quality tea on your own when you don't want to risk being stuck with several 100 g bags of something you are possibly not going to finish. Not to mention the cost it involves. That's why my progress in exploring other types of tea has been slow.