Originally posted by WMCoolmon
The irony is that despite its heavy armanment, the Plato would be essentially helpless against placid asteroids. 
Something its enemies could easily exploit with its low speed.
That was intentional with the weapon choice though. It allows for relatively safe escorts as buffers rather than an all out shooting match between typically anti-capship large vessels and asteroids. As a fighter pilot you don't really want to be in the line of fire of a dozen flak guns or large beam weapons. This gives the mission designers some more play with strategy where you could have large vessels escorted by a fighter wing or two and several small cruisers through a large asteroid field.
It also opens up the largely untapped class of small cruiser which would be ripped to shreds by a destroyer but would be perfectly suited to the escort role with it's weapons and size better designed for fighter and bomber suppression. Rather than having a ship with a lot of flak guns and a couple of large beams you could have one with a good mix of anti-fighter beams, a few flak guns, and some rapid fire laser turrets. In a bomber you can pretty much walk right up to most destroyer class vessels and have at it, but a ship like this would eat you alive.
EDIT: Just so this post will have
something to do with the Plato

... You probably wouldn't send a science vessel out on it's own, unless you actually want it taken out. You would want fighters or some other light escort with it to provide support. Giving the Plato weapons suited to defend itself against large ships is a good thing but it is a science vessel after all so haveing it armed to the hilt doesn't make much sense.