I understand speeds are being tweaked at the moment, but as the Archimedes is tuned towards a higher-end specification, will there be engine upgrades beyond what it is fitted, or will the engines/thrusters fitted be the best for that sizing?

There's definitely going to be room to grow, not only with the Archimedes, but with all of our ships. While the included equipment will put the Archimedes ahead of a Merlin in terms of its speed and performance, we absolutely want to provide enough tools and choices for players to experiment on their ships with.