Higher plans include more server resources (#1 factor in the WordPress optimization guide). Here’s the full comparison chart, but GrowBig gives you about 2x more server resources than StartUp, and GoGeek is semi-dedicated hosting which gives you even more. GrowBig and up comes with a free migration, staging, advanced caching, and ability to host multiple websites. GoGeek comes with priority support. Their cloud hosting is quite the price jump at $80/month.
StackPath – CDN with 31 additional data centers (Cloudflare has 150+ data centers, but more data centers = faster content delivery). I get around $1,000/month by referring people to StackPath in my cache plugin tutorials. StackPath recently bought MaxCDN and their affiliate acceptance rate is much lower (depends on your potential volume) but most cache plugins converted to StackPath as their recommended CDN
The problem with affiliate marketing, like many other home business options, are the so-called gurus and get-rich-quick programs that suggest affiliate marketing can be done fast and with little effort. Odds are you've read claims of affiliate marketing programs that say you can make hundreds of thousands of dollars a month doing almost nothing ("Three clicks to rich!"). Or, they suggest you can set up your affiliate site, and then forget it, except to check your bank deposits.