I want ability scores to be king in Variant but secondary stats will be needed to avoid too much interdependence.
I don't want hit points to scale in Variant. Therefore Hit Points will be determined with a simple formula of CON + Class HP, identical to how Dungeon World handles hit points. Ability scores will range anywhere from 1—18 and Class HP will range anywhere from 4—12, meaning a PC's hit points will range anywhere from 5—30.
I use a similar system in my 5e campaign, and in my experience it puts players in a daring but cautious play style—willing to charge into harms way but completely killable.
Known as Defense in most GLOG-likes, Armor Class will be a number ranging from 1—10 and will alter the target number (which is 20 by default) to hit you. The formula is Armor + Dex.
Armor is comprised of light, medium, and heavy; and grant +2, +4, and +6 Armor respectively. Shields are also a thing and grant +1 Armor. A naked PC has 0 Armor.
To write down your armor class, just add 20 to that number. So a full-armored PC with maximum DEX will have an AC of 30.
PCs have a number of inventory slots equal to STR. Item weight is tracked by slots. Small items such as jewelry weigh 0 slots, but stacks of small items can add up to multiple inventory slots. Items about the size of a medium weapon such as a longsword, quiver, scroll, and torch weigh 1 slot. Most things bigger than that weigh 2 or more slots.
PCs can carry weight in excess of their inventory slots, but each slot in excess increases the target number for movement-based checks by 1.
Things I'm not including
Attack, Movement, Stealth, and Save will be absent from Variant. These stats always felt like necessities of GLOG's resolution system and I found myself just calling for a simple check instead of calculating the target number.