I clicked this topic to suggest Hunky Dory. Along with Aladdin Sane, Ziggy Stardust, and Diamond Dogs you get the best era of Bowie.
This is kinda weird, but I'd also recommend checking out some collections that have B-sides and Bowie performing songs that he wrote for other acts as well. He has such an expansive body of work that it is really easy to miss some gems like Bombers.
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