1: Loadout Screen. A minor quibble, but having to replace default weapons with better kit is a little irksome. I always replace stanard issue stuff with the latest kit 'cos the player will obviously want it.
2: Messages. I think the initial messages between Ionas and Alpha were a little too long. And I doubt if the Ionas really needs to inform you as your wingmates die (though I can see why you put that in)
3: Gamma3, You forgot to make the Artemis scanneable!! Plus, I didn't have time to really check it out anway. By the time things had gone quiet it was too far away and I couldn't be arsed going back. I would make the scanning of Gamma3 the Shivan's cue. I like the idea though. (be a good opening for a mission in it's own right)
4: I didn't really know why the Ionas was waiting round. Maybe you could disable it and have the engines gradully repaired.
5: Pace, The mission was alittle short but adding slightly larger delays between wings would sort that.
The balance was pretty much spot on though and I thought it was a good opening mission. The corvettes don't play a major part in the mission though I doubt if they could without spoiling the balance (I'm working along those lines for mission2 BTW)
Which should be ready soon, so you can repay the favour

edit: oh yeah, try increasing the gap between messages as I missed most of 'em and make the Ionas an escort ship.