The 30% number is a general goal, as opposed to terrain vs. ports. It's hard to define it in terrain because there's high value terrain (where many ports are) and low value terrain (broader, empty ocean). The overall goal, of course, is to provide sufficient PvP that if you just want to play PvP every day, you have it there to play, and if you don't want PvP, you can reasonable avoid it.
People get very excited about these changes that we make, but it's still too early to really be passing judgment on how it's panning out, because players from other games show up with different models in mind. They assume that they have to level to 50 to be competitive, and they also try to take their best, most outfitted ships into PvP. Neither of these are entirely wrong, of course, but people will eventually learn that PvP can be played at any level, and that by default you should be taking cheaper ships into PvP, and leave the high value ships for the big moments where they really matter.