My homebrewed tabletop RPG isn't something you'd find in a weighty tome. If I were to put it down and publish it, then it would be about as think as the original pamphlets for Dungeons & Dragons or Traveller. Therefore, it's what some of you would call "rules-lite" (and what sets The Gaming Den off on tantrums of autistic screeching).
First, I'm using the Six Holy Stats of D&D: Strength, Intelligence, Wisdom, Dexterity, Constitution, Charisma. I'm using the 3-18 range, and rolling on 3d6 to get me that classic bell curve of distribution. That bell curve, and where your man scores on it, is a big factor that informs my rulings. It's part of my reasoning metric for determining throws.
Second, I'm throwing areas of competency together into vague categories and putting them into three grades: Familiarity, Competency, Mastery. The first is "Can do it", the second it "Can get it right", and the third is "Can't get it wrong". This is another part of my metric for rulings and determining throws. The categories are vague because this is meant to handle all of my gaming needs, even shit like RIFTS.
Third, I'm defining gear in real-world terms even if the gear itself is unreal (e.g. a lightsaber). So, instead of looking shit up in Fat Fantasy Splat Vol. 34: Left-Handed Bohemian Ear-Spoons of the Wanker Gods, I can hit up the relevant Infogalactic, Wookiepedia, et. al. page and figure shit out from there. Less paper, less paperwork, less jargon, more organic reasoning and thus better emergent gameplay that's normie-friendly.
Then there's the throws. Fortitude, Reflex, and Will (the d20 System saving throw categories) work just fine for me, so that's what I'm going for. I'm chucking rolling damage dice or having an Armor Class, and there's no defined progression, so these throw categories aren't listed on your man's sheet. Neither are there any Attack stats, or skills stats. Instead, I'm sticking to natural language that your man would use in situations as you would if you were in those same situations.
I'm unsure if I want to use the d20 or just stick with a handful of d6s for throws; the latter shows the influence of Classic Traveller in my thinking, but for a flat distribution of probability the d20 works fine. Hell, I'm thinking that 3d6 or 4d6 may be sufficient for what I want to do; I'll try some variations to see what works.
Yes, scaling is in effect, but it's going to be in natural language and not game mechanic jargon. You're not going to take on AT-ATs with a battle-axe, and you need not worry about the Yamato trying to swat your fighter with its shock cannons. I'm the GM, so I'm going to tell you what to throw and when to throw it, and why if I deem it necessary. Which brings me back to the key point: the strength of the RPG in general, and tabletop in particular, is the ability of the GM to handle all the complexity and make rulings on the spot that best handles the question of the moment.
My homebrewed RPG is nothing more than a framework to inform my rulings and resolve moments of uncertainty. Nothing more is required of a RPG.