You can keep citing numbers, if that's where you're most confident... but rationally there are other factors that can also be considered in context that aren't always quantifiable.
I haven't even looked at the stats of the Dbacks or Sox pitching staffs, so I believe you that neither is very good. But conditions in the majority of ballparks they frequent are quite different.
I'm not going to get too much into my past, but will admit playing on several professional diamonds with and against ex-pros or DI players all over New England and Arizona for years. Dimensions of fences in the latter are much deeper because the ball travels further; in places like Tempe Diablo and Scottsdale it's 360 feet down the line. The ball travels faster, too, because the dirt is like red gravel and the natural "grass" is baked into crunchy turf... both also offer rug burn raspberries for those inclined to slide or dive.
You may be aware that Phoenix set a national record as the hottest city last July, with average highs of 114.7 degrees. You probably also know from following the Red Sox that it rained for basically four straight months in New England. Extreme weather causes extreme conditions.