One reason to pick out the missiles early even if you can't shoot them is the tracking time bonus. The longer you have them on scopes, the higher bonus you get (also dependent on the tech level in missile tracking time bonus, of course). Might not be much at low tech, but every little bit can help in the numbers game against missiles.
And there's a button somewhere on the class design sheet to dump all your designs to a text file in the Aurora folder. Can be easier for exporting designs, depending on your preference.
Otherwise, I second (and third, and fourth) other folks: totally respectable low-tech surveillance and targeting ship. I'll be interested to see what the accompanying ships in its task group will be.
Edit: Oh, and for the 4x fire-con: on the research page, the (I think) 3rd and 4th dropdowns allow you to go up to 4x for range and up to 4x for speed. So if your base tech level Fire Control speed is 2,000 km/s, you can quad the size and get it to 8,000 km/s. That's a hard limit for fire control, is 4x your tech level. Turret tracking speed can (theoretically) go much higher than the turret tracking tech level, but it becomes unworkable pretty quick.