In regards to testing
The requirements for the Honbu Aikido Dojo in Tokyo can be found on their website. The Hakodate Dojo follows these requirements very closely.
As I understand it, in Canada and the US, there is a national body that defines the testing for each rank. Or, a dojo will have an affiliation with another dojo and use that dojo's testing system.
As to the question of a time requirement, yes definitely should have one. This would help reduce the number of people that only show up at testing time.
One thing that I would like to say is, if you are going to test the same technique at different levels, please xhange the type of attack. I have seen testing requirements that have shomen uchi ikkyo at ever level. This is not necessary i feel.
Just my opinion