1. The RNG aspect of the game is fine. It makes games interesting. No two games are alike because the games never spawn the same way and because you always start out in different sections of the map. Sure, the RNG can be a little annoying when all of the nodes spawn on one side of the map, but chances are if that happens for one GC, the other two GC are going to come in and stop them from obtaining a huge lead. It works itself out eventually, and even if you get bad games, you get good games that work in your favor, as well.
2. There has always been chaos in Frontlines, this doesn't pertain specifically to Seize. You've always had people running off and doing their own thing whether or not it would actually be beneficial to their team, whether that was in Secure when people would join the wrong alliance and head for the wrong area to capture (or just plain go wherever) or Slaughter, which in of itself was a complete mess with so many people running around in such a small area. Seize can be a little chaotic, but this is nothing new, and it's much more orderly than slaughter ever was.
3. It's up to you to try to arrange some sort of coordination for your alliance so that they know what to do and where they should be going, because sitting around silently and not saying a word is not going to help anyone. While I will agree that the mode is more favorable to Ranged DPS and Casters, ask for help from your healers, but don't become overbearing on them. Work a plan out together and move forward from there, but don't be like, "Hey you, healer. Yeah you. You follow me, got it?"
As for a meta, it's hard developing one for Seize because everything IS so random. Ideally people will start heading for specific locations in the beginning to try and maximize their range potential, but it's not like secure where it was the same A goes left, B goes middle, C goes right every game. It's different.
Seize is all about what you try to make out of it. It can be a little chaotic, and it can be a little annoying, but it's how you respond and react to those specific situations that changes the outcome of the game. Plenty of people will tell you that the RNG can be overcome with relative ease, and that the node spawns aren't that big a deal if you work together. However, if you sit around and sulk about how all of the new nodes are across the map, yeah, you're going to have a bad time.