Umm, no. Gravity weapons are a welcome tech tree as some players advance to Astrophysics 2 early on (to get sensors, null-space, whatsnot). This weapon indeed has a rapid damage drop, but when you make the ship well (on max-tech a battleship can be virtually invincible - absolutely destroys enemies in no more than 2 shots... and its design is easy to get in non max-tech game)
it is an understimated weapon. It is a weapon for planets and bases, but especially for those little nasty sats and/or bases and/or ships guarding WPs. Does low range mean anything to you?
