1.85; Lanchester, Castle - 13(4hrs till 14)
2. Minister
4. Honestly I would base it on age. Merging servers of the similar age, with the assumption that the average player level is also the same. If you merge the three oldest servers, and keep the chain going then it might work out. Since it seems servers are about the same age, then merging the three oldest would work. When you merge them there should be a warning, say a full week. When the servers merge it should be a fresh start in so much as everyone keeps their castle level and all they have worked for but gets a new chance to pick a kingdom. Possible pick new starter heroes, any ones payed for would remain and if new starting heroes are chosen then they start at level one. Also have it repopulate the map with new PvE of a much higher level. Maybe with a tiered system so that it is based somewhat on your castle levels. Thus giving everyone something to do while cities are being taken, houses are being formed, and politics are happening.
Also it would be great as previously said. If accounts that are inactive, say two weeks or more are sent to a purgatory of sorts. Where the accounts are not deleted but they are not automatically dropped into the new merged server. They get put into a holding bin, and when or if the player comes back then they can choose which server they go to. Either into the merged server or another one with which they are in the same as the average power level. Thus having less people and lag in the new merged server.
Secondly if a server is merged give the low end players a chance to not join the merged server. Give them the option to join a newer or lower level server. Since the point of merging is to keep things fresh and have high level players a chance to fight people on their own tier/level. With the added bonus of making much smaller numbers on any new servers. Once a server is merged new players are not allowed to join it, possibly hiding them from the server list. Thus keeping a more level playing ground with the titans having full court to fight among themselves. Maybe give merged servers a larger map to play with, since it will have more active people/houses. That would give houses more cities to take and more room to play in. Make the no-mans land higher level so it takes more time to take cities for the kingdom. Really anything you can do to stretch the game play for the merged server.
Eventually have the three oldest merged servers merge again. Say do it every three months to keep the game fresh. Sort of like a season if you will, how other ranked games do it. Somehow giving prizes to the people at the top of the leader board, not just players but also houses, and maybe Kingdoms. So it would give people a reason to keep working and fighting to stay on top. After a few rounds of this then end the servers. Award final prizes and let them start again on newer open servers. Give them medals or something to have bragging rights and maybe bonuses to help them rebuild faster and have an edge on existing players for a time while they rebuild.
5 - Well I would have two issues, one being lag and server insatiability. The servers are bad enough if you double the load and don't balance the game so the servers can handle the load. You only make a bad situation worse, in that people would just get fed up and leave or start anew on new servers and make those servers have the same issues and start a never ending cycle.
My second concern is the lack of an end game. Every game needs some sort of end, merging servers just prolongs your problem but does not fix it. I know you want people to play this game forever and continue to pay money, either Patron or outright buying Lunari. Since obviously you want to stay in business and you need customers to do that. However with no end game or reset in mind, then it is just and endless grind till people just get bored and quit. Eventually that sort of way of working gets toxic and can kill a game. I dunno how you make an end game, maybe just do seasons like I mentioned previously. Regardless there has to be a light at the end of the tunnel,eEven if that light is just a lure to make you start down a new tunnel.