It seems like you could accomplish the same thing more easily just adding xp awards to the existing system:
Explore a location/influence an NPC below your Tier - Award XP for defeating an Easy combat encounter
Explore a location/influence an NPC at your Tier - Award XP for defeating an Medium combat encounter
Explore a location/influence an NPC above your Tier - Award XP for defeating an Hard combat encounter
Nitpick: note however that there
is no canonical award for defeating an Easy/Medium/Hard combat encounter. A Hard encounter for four level 6 PCs ranges from 3600 to 5599 adjusted XP, but the actual XP earned and awarded could be anywhere between 300 XP and 20,000+ XP. On the low end, thirty bats who surprise you while you are climbing an underground cliff face in the dark are 300 XP, x4 for there being thirty of them which makes it just barely Easy, plus one difficulty level for surprising the party, plus one difficulty level for being favored by the environment (immune to falling hazard, immune to darkness), for a final rating of Hard. On the high end, an ancient black dragon is 33,000 XP, which is Deadly at this level, but if the party surprises the dragon while it's sleeping that bumps it down to Hard, according to the DMG.
Anyway, I think you're kind of missing the point. We've
all experimented with different ways of handing out XP, whether by giving out extra XP for fighting multiple enemies at once, or giving out XP for treasure, or something else. This UA is about tailoring the XP system on the
requirements side to suit your campaign goals. What you see as unnecessary complication is actually the whole point of the exercise.