Welcome to the DhO, Jake.
I'll just say that buddhist meditation practices usually have preliminaries designed to stabilize the mental faculty and to establish a moral footing. These stabilizing and grounding practices anticipate the likelihood of mental hardship that comes up in meditation (and life) and offer a means to prepare for those hardships skillfully and to help practitioners avoid compounding the hardships with more self-induced troubles.
In Southeast Asia, there may be a greater prevalence of Theravaden lineage, and the preliminary work is
concentration: one suffuses themselves with sukha through several mental 'states'. Moving to the Himalayas, the preliminaries are
ngöndro (about which I know next to nothing, but this youtube clip has a guy who can say the 100-syllable word, so maybe he's a decent internet introduction to their prelims).
Can you just have the 3 characteristics as a theme song that is playing softly in the background while the main focus is pure awareness that is constantly morphing?
Anything is possible, no? Perhaps try doing that: main focus as pure awareness (whatever that means to you and by whatever means you've found). If something later arises that is not playing softly, but is seemingly loud/hard to bear/dissatisfactory, then you might look into a tradition's map (monotheistic, vedic, etc) and see what might help.