I agree that space ratio is a significant factor, but you are comparing older O ships. To me, they are less attractive (smaller cabins, tiny showers in standard cabins, so PH is almost a must, less dining options etc). We sail on the newer ships only (Riviera, Marina and Vista), and those ships have much better space ratio (closer to SS), good size cabins, more dining options etc. Riviera never felt more crowded than Spirit or Dawn - in fact, I would say that the buffet on SS felt a bit more crowded than on Riviera.
If you looked at the older O ships, I can completely understand why you looked at PH (and the pricing is really not competitive in my opinion), but on the newer ships standard balcony is 240 sqft, which is more than sufficient, and if it's enough for you, I believe it's a better value than SS.