Probably my all-time favorite band behind Judas Priest. More people need to know about these guys, because they are quite possibly the most consistent band in metal.
Some great inclusions for sure. I'd add some well known stuff:
Running Wild - Death or Glory
Virgin Steele - The Marriage of Heaven and Hell Part Two
Lost Horizon - A Flame to the Ground Beneath
Labyrinth - Return to Heaven Denied
Stratovarius - Visions
Angra - Holy Land
Sorry, but YJM's Trilogy is a snoozefest. I was a monster Yngwie fan when that came out. I wanted to like it but just couldn't. Still can't. I think the best Gamma Ray's record is Land of the Free, although Somewhere isn't far behind.
Pretty sure my #1 power metal album is Fairyland's Score to a New Beginning (2009). It's completely keyboard-dominated -- the keyboardist/main-songwriter lost or fired the entire band and did their third with some hired hands -- and the results were impossibly cheesy but also irresistibly powerful and catchy (for me anyway).
Don't worry boys, these are just a few albums I love. I still have a lot of shit I need to get around to listening to. Still can't believe I forgot a Virgin Steel record though. That is inexcusable.