[Need Advice] Dropshipping Noob - My niche ideas

Personally, I'd go after the niches with the biggest profit per sale. That leaves you room to advertise and instantly start driving traffic and making money.

All the rest of the things you mention are not important. Having a blog or not isn't going to affect your sales. Having a few stellar, pillar pieces that can attract links is important, but they can be store info pages and not necessarily on a blog.

Because of that, choosing niches that you like, find interesting or are knowledgeable about is unimportant. I guarantee you that if you start making money, you'll become much more passionate about anything you are selling. If you're not making money, your passion really doesn't matter much.

I'd pick the one that looks like it would have the best profit per sale (usually the one with the highest priced products), buy a domain name and then start contacting brands to see if they will dropship for you (or recommend one of their distributors to contact).

After landing my first supplier, I'd build the website and would definitely not be using WooCommerce for eCommerce. I'd use a much more secure platform like Shopify, BigCommerce or 3DCart. Then, once I had a site up that looks like I am selling things and making money, I'd continue to contact other potential suppliers, trying to expand my product line.

There is a free trial you can try with Shopify, the web hosting is included with their monthly fee. Oberlo is an app you can use within Shopify to add products, you can review # of orders and go from there (learn about e-packets shipping).