I understand that you want to encourage new players joining, but I have would see some issues with this, as well.
I have just encountered someone beign a successful multi, cheating that is, and actively maintaining two provs at the same time. He didnt seem to get caught by IP. And I hear about kingdoms have been run by 3 people, all using proxies or whatever. All these people seems to now get a, potential, bonus, and a heffty bonus at that.
My impression, from what I hear, and have experienced, admins do not have a good enough grasp of the potential multi abuses. There are more technical workarounds then the ones suggested above about gonig to the library, I quite sure of. It means this could not be implemented wihtout giving the cheaters even more cheating bonus, as far as I understand it.
Also, to get freebies to those amounts can be close to game changers if a whole/half kingdom has em. As opponent it would be impossible to know, and silly if u lost a 2 week war cause of that. This would be a seperate issue from the one above, but they could also be one and the same.
One solution might be to significantl lower bonuses.
---> maybe to just allow these bonuses first week... not the whole age.
---> make a one time off bonus, of provinces choice, not a slight bonus all year.