You seem to like some "classic" 80-90's metal/rock (that's my favourite stuff too)
Maybe..
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Skid Row-
Helloween (the origin of power metal since you have Kamelot on your list..)
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Stratovarius (next step of power metal)
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Loudness (with Mike Vescera - also the best guitarist to ever exist, Akira Takasaki, here)
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X Japan (It's ~38 minutes in Live

)
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Hanoi RocksActually only Skid Row is American, but others are mostly with english vocals so no worries.