Let's take your info regarding the Yoga niche - I am thinking of making a main Word Press page myself and then build individual pages using software mentioned on your blog called "speedxxx" (can't remember full name 555) These pages can be quickly constructed and easily linked to each other via contextual links. Obviously making sure each page-product are closely related plus the normal traffic generation techniques, do you think this is a viable way to build an authority site Stuart and also overcome this idea that some Amazon products sell whereas some don't?
You’ll make more money in a niche topic than you will on a general topic for two reasons. First, you’ll be speaking to enthusiasts, people who live and breath the issue you are dealing with. They will be interested in what you have to write and in what you have to sell because it fits into a topic that they already care about and because you are promoting high-quality, expert content. Marketing to them will simply be easier.
Of course you want affiliates with high commissions, but they should also have a solid reputation with high conversions and low reversal rates (you get $0 if people cancel after signing up). If they’re part of an affiliate marketplace like ShareASale or ClickBank you can see some numbers there. Companies likes Amazon/SiteGround are safe bets, otherwise do your research (or track your affiliate links so you can monitor their performance). Avoid affiliates offering huge commissions since this probably means they’re struggling to acquire/retain customers naturally. This will hurt your numbers (specifically your conversions/reversal rates).
If you’re in the WordPress industry like I am (whether it be design, development, or SEO) I have accumulated quite the list of WordPress affiliate programs. I excluded those I found unsuccessful or pay too little to make a profit from, specifically ThemeForest, Creative Market, and low quality theme stores like Template Monster. Hosting pays well and I wrote a tutorial for SiteGround’s affiliate program and StudioPress themes which are my 2 highest paying affiliates. Those tutorials have tons of screenshots/social proof especially for SiteGround.
Cooperation with partners always brings positive results, especially when selling goods with minimal expenses. About affiliate marketing, I first found out in Madcash's blog. In which, in a very accessible and understandable form, detailed information is given on how to place advertisements on its website. Money can always be done if all efforts and tools are made to achieve this.
Always disclose your affiliate relationship. Most visitors will probably understand that graphic ad will lead to your getting paid, but if you write a review or use an in-text link as a recommendation, you want your readers to know that may lead to compensation as well. This ensures you retain transparency and trust with your readers, but also, it's required by the FTC's endorsement rules.