Thank you! I'm definitely planning to add more artefacts later when life's less hectic. As for the structure, I was trying to leave it more open for the GM to come up with a story to tell. If they wanted to make a more mystery based game or spy-thriller type they could.
The ship mechanics are a bit weird but it's mostly to a) force the players to go back to the ship and take a moment to think about what they learned and b) a slight punishment for not handling the artefacts properly. The changing the power supply is also supposed to be a way to signal that the party is ready to get the artefact (and, if they identified it wrong, the beginning of a mad rush to collect the items needed to secure the artefact correctly before the engine overheats). I hope that clears things up with the ship mechanics -- I'll be sure to edit that part in an update later.
Thanks for the feedback! It really means a lot to me :)