I think ability scores are not needed for monster blocks.
Maybe something like:
- Set HP
- Armor and saves
- speed
- Passive stealth, Passive perception
- Attack routine
- 1 special trait or ability.
It's pretty rare a monster has to make a skill check, even more in 2024 since grapples and such are a save. A passive score for stealth and spot is probably enough in 90% of the cases.
Ex:
Town Watch (lvl 1 humamoid)
Armor: 14 [if shield +2] HP: 11
Defense Saves: str +3, dex +0, con + 1, wis +1, int -1, cha -1.
Speed 30, Initiative 11 Surprise; 9 Spot; 13 (dim-light vision)
Attack: d20+3, 1x [W]eapon +3