Hybrid mechanics are imbalanced.
Playable without high level requirement:
1h/hoplite: flexibility, wpf
1h/2h/pole: flexibilty, wpf
1h/crossbow, 2h/crossbow or polearm/crossbow: ranged weapon and melee, light armor or wpf penalty
melee cav: horse, -2 levels compared to dedicated build (riding skill)
ranged cav: bump damage, survivability, -2 levels compared to dedicated build (riding skill)
Really weak unless high level:
thrower/melee: gets throwing weapon and melee, loses 2 levels from PT, has low range so melee is a must and heavy armor a desideratum (accuracy penalty...)
archer/melee: gets bow and melee loses 2 levels from PD, carries 14 weight arrows (~6 AGI + 2 Athl lost)
However, most archers are dedicated archers because dedicated archery is playable. Throwers are usually hybrids because playing pure throwing without melee is barely viable since range and ammo are low, and it looks pretty ridiculous when some berserk axe thrower glances on medium armor. So I support you, OP: Even though throwing got some buffs lately and throwing lances became pretty nice, it is still not as strong as other classes.