I picked Gryffindor when I started the game, but I lost my phone and had to restart, when I did, I choose Slytherin, but after like 1.5 years of that, I decided that I did not in fact like it, didn't feel right. So I made a new account with Gryffindor again. I felt like you first. "So many hours", but then I realised that in the end it's just a game, and even tho I lose all the nice outfits from events, and all the sleepless nights I spent for events will be wasted and so on, it doesn't matter in the end. Now I got my new account, and it's so much smoother. Doing better choices early on, (like grinding the heck out of attributes), and I have no regrets.
It sucks losing all your progress, especially since you spent most of the game farming attributes and books, but playing the game in a house you're comfortable in is better. :)