First of all, there are no map where beginning rush is diagonal. There is total 3 types of rushes: Front Rush, Side rush and Diagonal Rush. And as I reckon diagonal rush in solos and doubles map is only present in Lighthouse and Nutcracker. Rest of the maps only have Front rush or Side rushes.
I mostly like to rush the side which takes the least amount of wool. But sometimes if I don't have any first rush then I like to go to my 1st rush base and gather the resources from his/her generator and then I return to my base and bridge to Diamond Generator and buy proc and then rush the 2nd player closest to base. But sometimes it depends on the game for example if I am in game with a player with high skill or level, I like to go for them and eliminate them first.
Pro Tip: If you don't have a first rush and you have queued in a map like gas station or speedway then it's a great time to complete quests in which collecting diamonds and emeralds is the mission.
