I actually just logged in to suggest this very thing.
For many things where a user wants a pattern fill layer style the only workaround is to create a new pattern at the desired angle.
For shapes it's easy enough to just dup a layer, apply the pattern fill, rotate the layer, then mask. But when applying a pattern fill to things like text (which will undoubtedly change later) multiple layers can be cumbersome to manage and re-mask should changes occur in the text.
The ability to simply set the angle of a pattern would not only cut down on the necessity to manage multiple layers with associated masks, but would also cut down on the amount of patterns needed to accomplish a given task. A user could have a straight, single pixel, vertical pattern then be able to use that one pattern tile for any single row pattern they wanted whether at 45°, 90°, 30° or whatever.
Since this is regarding pattern fills... I'd also love smart object patterns. Double click a pattern swatch and it opens in Illustrator for adjustment. I know, probably left field... but you never know until you say something 😉
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