There isnt really a right or wrong recipe. There are guidelines you can follow, but at the end of the day soap calc and experimenting are the best tools to find what works for you in your recipe.
The Zen single soap swap (sorry dont have link handy but it can be googled) gives you an idea of what oils bring to your bar and what dont hold up well in soap, and thefore should be kept to a minimum (less than 10% or not used at all)
As for the oils you mentioned, they are all pretty stable and can really be used at any percentage.
Coconut can be drying if used at higher percentages than 25 - 30, but you can counteract this by upping your superfat.
Castor - can cause a sticky bar if you use a high percentage, so it is usually used at around 5%, however I have heard of others using higher.
Olive oil - takes a while to cure, and can cause a slimy bar, but it is gentle, so it depends on what type of bar you are going for.
Palm oil - I don't use Palm any more but used to use it at around 20 - 25%, it makes a nice hard bar, but I'm not sure how high you would want to go with it?
I hope this helps