Since I love the idea of logistics being a central aspect of the game, using an island switch to a different town as save transport is a problem. On the other hand not being able to switch the free island travel to the home town of the guild I just moved to is a problem too. Giving up the island and starting new is a needless grind and no fun at all. Games should be fun!
But there is a simple solution:
change of home town for private island is necessary, so it should be possible
restrict switching frequency (e.g. once every 30 days)
there should be a moderate fee in Albion Silver (e.g. 25% of accumulated upgrade costs or even less)
switch is only possible, when no hero is on the island
after the switch all inventories and all farming patches are empty
So if one wants to keep the stored stuff, it has to be moved by transport before the switch takes place.
Albion Silver cost and moving time should be scaled with size of the island, number and tier level of buildings/plots. Maybe some cost from distance sounds also quite reasonable, but not necessary.
So this moving should not be instant or free, but the opportunity move to another location without starting all over again should be possible. All possibilities to abuse this moving system should be restricted so its just ment to players who want to move close to new guild for example.
And hey this kind of moving system works also as a bonus Albion Silver sink