It seems to me that the nanoripper blows the socks off every other weapon in the game. This weapon you get by going through the mass driver line from mass drivers to singularity drivers, and then at gravity driver I you also get the Nanoripper.
While the gravity driver does 3 damage, the Nanoripper does 8. It also have a relatively low space, and only costs about 3-4 times as much as a gravity driver. In the driver line, the Nanoripper is not outdone in its damage/space ratio until the very last two techs (which are also expensive weapons). In fact, you are better off researching better hulls, miniturization, and defenses once you obtain the Ripper.
In my games as well, I have seen little reason for using any other weapon once getting the nanoripper. Even if the opponent gets a decent amount of mass driver defense the Ripper can overpower it with relative ease. You only need to make sure that your defense is decent against the enemy attacks. (Note that generally the Nanoripper is the best weapon even against mass driver attacks. If you have other weapons that do about 3 damage for every 8 you are doing, then the Nanoripper will do comparable damage if the enemy has 5 armor for every nanoripper you have, then you are dead even, otherwise you come out ahead).
Is it me or is this just wrong? Either each tree needs a weapon like the nanoripper, or this weapon needs to get removed.
Also, it seems like the AI never uses this weapon--even if they have the necessary tech, which is often a fatal mistake.