There is a bug with pirate still.
A potential sub with a pirate plus another +speed specialist cannot target an enemy sub that would otherwise make it to their base before a sub with just a pirate would get them. In the game I am in the middle of right now, I could take out a sub loaded with a queen by using a sub of mine, armed with a lieutenant and a pirate. However, when I try to target the enemy queen sub, it would get there a couple minutes too late and so I don't get to target it because just my pirate alone won't make it to the enemy sub on time. If I could somehow add on the lieutenant to the sub with the pirate, I could take out my opponent, but the game does not allow for that (at least, as it appears to me). So my purchase of the pirate did not help me, and might cost me the game. Meh.
For pirates, perhaps one way to fix this bug is to be able to tap on an enemy sub, and if you have a pirate in play, there is a button that says "target with pirate." Your pirate sub then targets that sub, and you can load whatever specialists you want onto the sub with the pirate. If at the time of the pirate sub's launch, it would not target a sub by the time it reaches its destination, then the pirate sub launches anyway, forfeiting the 2x speed for the pirate, and targeting the enemy sub's destination.