I already told this once, but in case you missed, here again:
Tip 1: Do it at specific few hours of the day
Open Field GxG is good! BUT you need to activate it only at certain hours of the day. 24 hours per 7 days its not only insane, its completely frustrating, because the Guilds know that after the First day no one will care anymore about protection since there is no way to protect the Tower all this period of time.
So, active this between 18:00 pm until 21:00 pm. .3 hours per day. Simple like that!
Tip 2: Optional extra tip 1:
Less importantly, instead the needing of Number of hits and tower have auto-heal, make it like 10Milllion Health, and players can heal it. Would be better know that you still can turn the table even receiving lots of damage, than lost your tower because a moment of 1 minute where no one could defend it, just at the beginning of the war. You can do even less, no one heals the Tower, but it has 20 million HP for an entire week.
Tip 2: Optional extra tip 2:
Much less importantly, and I say that because would be the only thing that maybe would be hard to program: give some reward.
The optimal choice would be to reward both sides with a mediocre reward, like '20 Health Potion LV 15" for each players of both Guilds. You can make requisites for guilds so that they could earn this rewards, like, the Guild must have at least 25 players, this way Templars with only 10 members will not start the war just because of the Reward. And since the reward will be mediocre, just to encourage players, there is not much risk on that.
OF COURSE, you could do a better reward for the guild that wins, but as a programmer starter myself, I know that is more difficult create measurements to know what Guild Won, Why, When and if this was fair or not. So, remember, that is not urgent, the WHOLE point of the other changes it to encourage players on PVP right now!, on getting back to the game, WITHOUT getting tired of the actual system, so don’t matter much what you win at the end, because players generally play this type of game and get better gears only to do that without thinking on the reward, they just want to work together for a common objective that is not PvE.

