They say the devil is in the details. Here are an introductory few, with comments. The comments are intended, not as answers, but as spurs for thought. Critical analysis will produce a sounder result:
A central feature of Active Democracy is that participants are required to physically meet with other members of their group. This detail offers benefits and imposes penalties:
Among the good things:
a) It allows participants to experience the non-verbal clues people emit when they communicate.
b) It encourages the discussion, dynamically, of current local, national and international events in an unstructured format. Such discussions tend to reveal the natural reactions of the participants.
c) It encourages spontaneity when discussing the more formal material supplied by the Election Commission ... things like pending ordinances and the budget.
d) It removes any possibility of ballot fraud.
On the downside:
a) It makes no provision for absentee voting. To accommodate potential absentees, it might be possible to add flexibility to group scheduling; i.e., let members who can not be present ask the other members of their group to accommodate them when setting up group meetings.
b) It demands time away from one's employment. This may require a law similar to that applying to jury duty and military service requiring employers to grant employees time to participate in the election process, without penalty.
c) It makes no provision for incomplete groups. Each level will have incomplete groups, those remaining after the participants at a given level have been grouped (one or two people may be left over) and those occurring because of the death or incapacity of a group member.
The Election Commission will use members of "broken" groups to complete other groups or form new groups, as appropriate. When all the groups have been set, any remaining participants not assigned to a group (possibly one or two people) advance to the next higher level, automatically. These one or two people must be the first assigned to a group at the next higher level.
When the system has matured (after multiple election cycles have transpired) those who achieve the first level of public office will tend to change from election to election while those who reach the upper levels of public office will tend to do so in subsequent elections because they reflect the popular preferences of their time while demonstrating the qualities we seek in our leaders.
However, the dynamic nature of the process, with random assignment to groups at each level, makes it unlikely that a person elected to a public office will be returned to the same office in successive elections. There are too many variables. Even so, a person who serves with integrity, intelligence and energy, is likely to be re-elected to some office.
Elected officials NOT returned to office
A person may rise to hold public office in one election and not reach that level again. Such people take time out of their lives for public service without career guarantees. That disrupts the individual's life unreasonably. Such people must be honored for their service, and, on a practical level, we must continue their salaries for some period (a year?) and support their transition to private life with something similar to the G. I. Bill of Rights ... advanced education, career training, small business loans, and so forth.
These are just a few of the details that must be considered. There are many more.