IIRC the Resources folder is sort of not best practice / legacy holdover from before Unity had streaming capabilities or access to things like asset bundles or www loading, so anything in there doesn't benefit from things like batching, compression, compilation or obfuscation and just gets bundled 'as is' with a build in its install directory, and you have to manually unload any loaded assets.
You can do pretty much everything that pseudocode does without using the resources folder just by manually creating a sprite array inside the editor for example, then explicitly referencing the array index either by rememebring what index each asset is, or by having a constants file (much better for readability and future upkeep) where you do things like
Code:
public const int SPR_MALE_FACE_1 = 0;
public const int SPR_MALE_FACE_2 = 1;
public const int SPR_FEMALE_FACE_1 = 2;
public const int SPR_MALE_FACE_3 = 3;
(a 'real world' example where I added a new entry to a series after I'd ended a series, but it doesn't matter because all scripts are referencing constants and I can just make a list of everything in my constants file called SPR_MALE_FACE_)