Are skirmishers too powerful?

[Dayve]

I'm noticing now as i start to fight against factions that use lots of javelineers, that they are extremely powerful... Sometimes even devastating, against my units which have large shields, i'm playing as the Romans...

Now i know that early hastati have no armour at all except for their helmet... But they have a massive shield... When my hastati are stood still and a volley of javelins is fired against them they take around 5-6 casualties each volley... (Large unit size) Now unless historically those javelins would penetrate Roman shields then this should realistically not be happening... The shield that the Romans carry is easily big enough to provide great protection againt missles... Especially slow moving missles like javelins, so if my hastati are stood in formation and raise their shields to stop javelins then barely any should get through... Where could they hit? They have a greive on their left leg, their shield is covering from their lower thigh up to their head, so unless they're unlucky enough to get one in the face then 6 men shouldn't be falling each volley...

Oh and one thing... I think Cartheginian and Iberian armies recruit WAY too many velites... I'm seeing full stack armies with over 10 units of velites in them... Although i know this might be difficult because i played around with units months back making them more expensive and stuff and i saw that the AI always recruits what's cheapest 90% of the time... Even if they are capable of recruiting better quality troops.