There are few things that you need to follow if you want to avoid getting penalized * If you have many blogs, then go for C Class hosting( Use Different IP address) * Just make sure all the sites are unique, nothing should connect the sites together ( Footprints) * Don't link to a commercial website more than once or twice. * Make sure that your Outbound Link Profiles are different. Place some high authority links like Wikipedia * Just avoid linking sites that has Google Ad sense or Google Analytics in it, because if you link to a site with Google code on it then they will get lot of info on your site. * If you are using Content Management Software for building your sites like word press, Joomla etc. Just use different themes and plugins.
Use a diversity of anchor texts in backlinks. Add quality content to get links naturally. I don't know if using different WP themes and plugins makes sense.
To do effective seo relevancy is main thing. Relevant Content and Relevant links is really helpful to get safe way.
Regarding the point about Joomla, make sure the Joomla core and any templates, components and modules you are using are always kept up to date. One of my sites got hacked because the joomla version was not up-to-date and the code got infected with spam links - which of course hot me penalised in Google.
These two are the most true out of your list and these are what you need to keep in mind when creating link wheels. Thanks for the list! Have a good day!
Don't spam on dropping links it will harm your site badly and don't drop link on sites that has been flooded with spam.
It's about doing it in time. If few years ago, few work was enough to get the trophy, well now, its not that easy. You need a lot of more work, and patience. I know that for many patience is not such a good and close friend.