Last summer I started developing my own method for staying ahead of the "AE logistics curve" when it comes to cargo ships and all the who, what, when, where and how much questions arise. It is one of your biggest tasks if not THE biggest when playing as Allies.
So I decided to modify
Kull's AE Allied Setup Spreadsheet last fall by adding my own
cargo ship minimum port size in column
K and a designation for what I call "Dual Cargo" ships (both
supply and fuel capacity) in column
G.
Here is a pic of the Tjilatjap, Java portion of it:
First, in column
G you can see in the heading
"Cargo: Supply & Fuel" and all I have done is use the common color of creme to highlight the Unit Model/Type data, such as Euro L Cargo, etc. You can quickly see that both of the Euro L Cargo ships in Tjilatjap, Java need a port of size 2 minimum to dock for loading and unloading.
Second, in column
K, denoted by the creme color, where "n" is the size port + the ship can be docked. This helps me quickly scan the spreadsheet page and determine which ships are best suited for certain jobs. Obviously as HansB points out, you would not want to send a ship that can't dock at a
Size 1 port (6000t max ship/6000t total ships), etc. on those missions, as they would have to try to unload direct to the beach. It can be done, but it is VERY slow (Max cargo tonnage/day at
Size 0=100t, compared to
Size 1=2500t,
Size 2=6250t, etc.
Obviously there are no zeros in the K column because docks do not exist at dot base or size 0 base harbors. Historically, the USN used Funafuti atoll lagoon as a staging area, but they had to bring up scores of lighters (barges w/ winches, etc.) in order to make it all work at all.
Another aspect one must consider is when transporting troops from the west coast to the south pacific, you need to keep your destination port sizes in mind. This can easily dissolve into a point where hardly any of your bigger USN transports or civilian counterparts are going to be able to dock at Pago Pago or Noumea (size 2). Only Suva has a size 3 port that handles up to a 12000t ship/max ships 24000t. In certain cases you won't have much choice. The troops are already loaded and that taskforce is enroute. You can reorganize it to some degree, or take the nuclear option and send the TF to a large port, unload everything and then reload it. This is another example of what happened in Wellington historically.
As mentioned previously, Naval Support is crucial to unloading heavier equipment. You must get acquainted with all the different Base Force units and figure out how many are Engineer, Aviation and Naval support or some combination of all three. It obviously won't do you any good to send a Base Force to a site that you intend to build up with both port and airfields if it doesn't have all three. You can send multiple BFs to accomplish the same job of course. Amphibious TFs will be mandatory for early supply runs to dot bases you intend to expand (so that supply is waiting when the BF arrives so they can work).
Don't forget your max supply and fuel stockpile limits on the smaller islands/atolls and the spoilage effect. Again, check your available ship tonnages and locations to make wise decisions when it comes to task force composition.
One last item - early war when you lack escorts, remember that the larger a task force is, the easier it is for IJN subs to detect. Unless they are a fast group, you risk losing more ships. It is tempting to slap 8 12kt cargo ships into one TF for convenience, but it comes with a risk.
Good luck!