Sorry I don't have any suggestions for you based on your very different climate and therefore tree choices. But I do recommend that you change the title of your post, since people won't know it is really about ORCHARD LAYOUT unless they click on it first. If people assume it is about ORCHIDS, the flowering plants, most on this forum will just ignore it because they will assume it is in the wrong forum altogether!!

Cheers

I don't think GW allows titles to be changed on posts but I assume most folks will read the title as I did - as a typo.

You will want to add some location information to your post. You appear to be in a warm area since you have both avocado and citrus, so you will need to choose varieties of your other plants that have low chill requirements. Blueberries are shrubs rather than trees, and so need to be placed where the trees won't shade them. How much space do you have? Is strong wind an issue in your garden?