Getting caught by a pirate fleet would be a straight up GG. You need to have some combat capability, or at least a decent chance to flee combat.
Mule has both. And probably the 2
nd best ship system in the game.
The only serious problem the Mule would have is being swarmed, which is same issue
every ship has when you only have one of them.
I do like the idea of having Sheperds being the trader start ship though. Dog freighters are even more of a trap than they were previously as almost all pirates carry ion cannons now.
Although the idea of a "civilian" destroyer is pretty interesting.
You could even make a
Hinny (A Mule but with parents the opposite way round); similar handling and armour, but a little smaller so it can't carry as much and a similar weapons load. Maybe drop the medium E to a small and lose one missile rack?
The important bit would be the handling and armour - the two biggest problems I have with frigates are that I just can't control them even with the turn-to-cursor thing on, and that they're really fragile and even a single hit in the wrong place can end you.
These two problems synergise to a really obnoxious degree in that the fragility of the frigate
can be mitigated by sliding around all over the place, dodging/weaving etc. but if you lack the ability to do that consistently then you are going to hit a big wall pretty quickly.
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And turrets. Being able to move freely and still shoot at things makes it quite a lot easier. Probably why I am such a huge fan of the Enforcer.