[Should we avoid anchor text for more than half of our inbound links that we set up? And instead, use the actual domain? So make the actual domain be the clickable link? I hear that this is more natural.]
My advice would be to stop worrying about trying to look natural and instead focus on being useful and relevant.
If you are just spamming your links all over the place, it isn’t going to help much trying to fool search engines by varying anchor text. They will devalue it no matter how “natural” you try to look. If you create useful content, to go with your anchor text, you don’t have to worry about how many backlinks you are creating, or how natural they look.
I know that spamming often does work, on a temporary basis. However, you must know that webmasters, moderators, search engine anti-spamdexing teams and search engine algorithm programmers are all working around the clock to find and delete, or devalue, everything you are doing. Sure some of it will stick for a period of time, but isn’t it a little like building a house of cards?