There are many people who decide to make a website or blog on more than one niche. However, you might consider this:
As you know a website is different than a blog and how you create the site and how the site is presented. On a website, you have web pages that will list some important data and hold the sitemap, your privacy statement, and your terms of the agreement.
On the website, you'll add site pages with some information on them that will redirect the reader to your blog.
Today you can add a blog/website in one location under one name. All you do is have a web page that goes directly to your blog site.
When doing this you should list all the different niches on your website, then on your blog spit them up to subcategories.
The only problem with this is the amount of work you'll have and the amount of information you'll need to write about to supply to your clients. Furthermore, a website or blog with too many niches is hard to get a lot of visitors to your site because you have a lot of different audiences to target.