In terms relative to human proportions, the spears should be about maybe 12.5% longer if we’re using the in-game character models to be like humans. But that’s for one-handed spears of course. In history there were different lengths of spears for different situations since it’d be somewhat useless to have to balance a long spear with one arm while holding a shield. It’d be too clunky, but that depends on the weight as well.
If the spears were lengthened to what I had suggested, they would be referred to as short spears.
Now, the Spartans are special. Since they actually did wield longer spears in one hand with a shield. But that’s mainly because they had underwent harsh training, and also infants that were chosen to be a Spartan went through an inspection with some kind of council. Mainly to check for any physical defects, even minor ones.