I agree with all the points you have mentioned. Talking about zero upsells, for instance, the best thing online, is setting aside a budget, and being able to respect that budget without exploding it. This is the amazing part about Wealthy Affiliate. You can plan 2,3,or even 4 years in advance and that budget will still be very relevant and applicable.
There is no autoresponder included. There are many affordable autoresponder services out there that you can get when you need it, but building an email list definitely should not be the starting point for your business. That will come down the road, typically when your website is getting a sustainable source of traffic. You will be learning all about this as you move through the elite, industry leading training at Wealthy Affiliate.
Hey. Yes you can use just one website to promote multiple affiliate programs, but I’d say that your website should focus on just one niche. So you mention, SellHealth, that would lead me to believe your site is about health and fitness. I would then advise you to stick to that niche rather than promoting unrelated products like dog leashes and fashion accessories.