Servers are won before they start...
And DH, you always take the path of least resistance. Basically, the server has WG, but as written, the admin is taken out of the picture in deploying them. The approach is novel in one respect, which I rather enjoy, you are telling the player base that it's time they act more responsibly. Unfortunately, there are players like myself who haven't won a server in years, always joining the losing side so we have more targets to kill. I hope you connect with the more responsible nutters who are the ones that need to take your idea to heart. GL.
People will generally find more happiness if they take responsibility for their own fun, and less happiness if it is attempted to be thrust upon then by an outside force. People play for different reasons and find their fun based upon those reasons. For some switching sides will best satisfy that fun if there is a lack of balance, for others such balance is not the thing that generates their fun. These folk could enjoy flying with their fleetmates, flying the ships of a certain race they have chosen as their main, or flying ships of a race for the first time. It could also be fun for some to fly on the outnumbered side, ie, flying against very long odds, or flying in a target rich environment. It could be still other factors, such as being a stragegist and planning a server long strategy through from beginning to end, watching it develope and making adjustments based on conditions, being a leader and motivating their team watching the cohesion grow as the server developed, being a loose cannon deepstriker and taking days or even weeks to set up a sudden and quick exploitation in the enemy position, etc.
The fact is, balance is nice and most people find balanced servers the most rewarding, but for some it is not essential for their enjoyment. I don't think balance generally hurts most of the other motives I mentioned greatly, although efforts to enforce it can do so to minor degrees, and therefore I prefer it, but it is not necessarily required for many of the players to enjoy themselves. A blowout, is a bit of another matter, and players need make their own judgements about whether to switch or not as Die Hard has outlined, but a lesser imbalance in itself has certain charm for some. I know AOTK was a bad situation for the Kitties due to numbers, but we managed to really have a great time even so and it ranks in my top 3 servers ever. If you have good company even bad situations can be wonderful and a defeat on the map is of no real consequence in such situations.