Finally completed my last naval treasure mission and got the Draenic Sea Chart. Took me about 15 days from finishing the 10 naval shipping missions to getting the chart. Used Mission Completion Orders on all 5 of the legendary naval missions to speed things up. Also emptied my 10k garrison resources, mostly spent on buying naval equipment for finishing the naval treasure missions. At the end, I was left only with 600 plus garrison resources and 380 oil. I ended up completing Boarding the Master's Call mission with a 95% success chance. I initially wanted to equip my epic destroyer and epic battleship with Unsinkable but had no more resources left. I rolled a rare carrier on my first try and decided to just gun for the Draenic Sea Chart. Luckily I had double Human crew buffs to boost my chances (though Pandaren crew buff would be slightly better).
Transport - The Hungry Riverbeast (Pandaren crew)
Battleship 1 - Thorim's Hammer (Pandaren crew)
Battleship 2 - Falstad's Return (Pandaren crew)
Battleship 3 - Mimiron's Folly (Human crew)
Destroyer 1 - Turalyon's Hope (Human crew)
Destroyer 2 - The Cutting Edge (Pandaren crew)
Sub 1 - Golin's Bane (Pandaren crew)
Sub 2 - Neltharion's Madness (Night elf crew)
Carrier 1 - Hammer of Justice (Draenic crew)
* Carrier 2 - Memory of Magni (Night elf crew) (insta-epic, added after getting Draenic Sea Chart)
Most of my ships I had levelled right from the beginning since I obtained the shipyard. The only recent ones were Mimiron's Folly and The Cutting Edge (a destroyer which I had obtained to replace Yrel's Command after it was destroyed on a failed naval treasure mission - The Hungry Riverbeast was lucky and survived). I had originally intended for my strike team for Boarding the Master's Call to comprise 1 battle ship and 1 destroyer, each with Pandaren crew, and an expendable Carrier which I would raise to epic. However, circumstances resulted in a strike team with double Human crew buffs instead. I estimate 3 ships with triple Pandaren crew buff would be around 96% success rate, as detailed here, and as calculated on Wowhead's naval mission calculator. (Pandaren crew is 2/7 better than Human crew). I will need to test out this theory with my Paladin on his legendary naval missions.