Hello good morning and welcome to WA. I too had the same difficulty. The idea is a mixed niche site at first to promote WA, and as you go you join affiliate offers and put in this site as well. If you get another site then seperate website for that one. But keep in mind the blogging must go continuously as you maintain many sites the so many blogs you must put each month. A great idea two sites one mixed niche and one specific would do as you can manage just see or one mixed niche site I have .

Yes Lee, I agree with John, pick the one you like the most and that which you know a lot about so you can write lots of content about it. Yes, music would be too general, what part of music do you like and know much about....singing, playing instrument and what instrument, or composing. Remember, you will be promoting that niche so it has to be something you are have knowledge about.

Hi, Lee and welcome to Wealthy Affiliate. What do you like the most out of the three? If you like them all equally, then ask yourself which one of those niches do you know the most about? You certainly want to pick something you can write about in detail.

Welcome to WA! The main criteria I use is do I know a lot about something and am I passionate to the point of wanting to share it and talk about it, and is there an audience out there that will want to listen. Heck, writing about football would give you endless material and an audience from around the world. Hope this helped. All the best to you.
Warren