I would agree with all that you said. But how come Indonesia is being charged 14 billion dollars for 36 F15EX? So how can we be so sure that F18 will also come at the price you quoted above. Can you breakdown the cost of 36 F15EX for us?
I don't know the price details of F-15EX offer to Indonesia. However, here is the USN acquisition costs for F-18 E/F:
The Navy intends to buy at least 80 more Boeing F/A-18E-F Super Hornets over the next five years to address its fighter shortfall, a change from its previous on-the-books plan to zero out the aircraft program beginning next year, the service said in congressional testimony today.
news.usni.org
"14 F-18 in 2018 for $1.25 billion , 23 in 2019 for $1.95 billion, 14 in 2020 for $1.35 billion and 14 in 2021 for $1.27 billion and 15 in 2022 for $1.28 billion." USN is paying $80-$85 million per new Hornet.
As you can see these costs do not include facilities, training, weapons or sustainment costs. No fighter jet can be assessed with only a sticker price without factoring in other costs. The other costs could be one time (training, infrastructure, modifications) or per flight hour costs that is total operating & support costs divided by total flight hours.
To get most realistic projection, Acquisition costs plus Cost per flying hour (CPFH) should be added. Note that cost of Gripen-NG variants is significantly higher.
As you can see the acquisition and operating costs of F-18 are excellent. Now let's move to weapons package.
All US weapons are NATO compatible that means, any NATO aircraft can (after integration and qualification testing) use these weapons. Due to its widespread use in Europe, all F series fighters have been integrated with European weapons however, same cannot be said about Euro-Canards. (For example, F-35 is undergoing integration with Meteor and NSM right now) but Rafale/Mirage cannot use JDAM.
Except Gripen and now Eurofighter, few spend R&D money to use US made arsenal. French aircraft are probably the least integrated of all. The result is exorbitant costs for buying nation in form of expensive French weapons or paying extra for integration of incompatible weapons. That was one of the reason for India to ask Dassault to integrate Litening/Spice with Rafale because Sagem AASM costs $300,000 per unit compared to around $30,000 per JDAM/ Spice.
From purely cost point of view, buying US weapons is always cheaper than any comparable European option. Economies of scale is a real thing! That's why allied nations continue to reap benefits of US investments.
Cheers.