Not exactly the summary you are looking for but hopefully answers some of your questions
I work with a number of search affiliates (by day) who are using SEO for search directory style sites.
All the big players use different IP’s and different a few different company names and whois details. The logic behind this for these type of sites is that they are SEO’ng search results on search engines which Google etc… really don’t like.
By having a range of sites on different IP’s means that if for any reason of there sites falls foul of the engines and ends up blacklisted or watched (yes the engines definitely do this) they are protecting themselves as this particular style of site wont last for much longer than a few months
So for a casino affiliate if you have a lot of sites as a precautionary measure I would split them up. This does not mean that you are doing anything particularly bad (scraper sites etc…) but if for any reason you get on the bad side of an engine or they think you should be, you have covered yourself. by not getting all your sites into the trouble
This is quite easy to do – In terms of getting different IP’s you could open a few different hosting reseller accounts from different companies and you can split your domains/sites between them. For a few sites I have I put them on a hosting reseller account where I can host multiple sites/domains its not expensive and can be as cheap as having one dedicated server or multiple single site hosting accounts