A simple mod that by default multiplies the ingredients, results, and crafting time for scrap recycling by four. In other words, the recipe results are always output in nice four item stacks without changing the recipe in any functional way. The amount it's multiplied by can be modified, in case you have a modded stack amount.
Alternatively the mod can divide the chance of each result while multiplying the amount output.
Mods that modify the existing recipe or add other types of scrap recycling recipes in the "recycling-or-hand-crafting" category also get affected.
If you know of or have a mod that adds a scrap-esque recipe that doesn't get modified, let me know and I'll fix that.

Quick disclaimer:
When a recycler first outputs from a recipe or when the belts they're outputting on are changed they might output an incomplete stack. This is due to how the engine handles stacked outputs and can't be easily fixed, but it only happens on the first craft cycle.

Thumbnail by BlackATM, aka Mr.SmoothieHuman. You should check out their stuff:
https://mods.factorio.com/user/Mr.SmoothieHuman