To clarify a couple of things in response:
Firstly, in all the time which I have been playing Chaos I have never proposed any type of tournament in which players are 'forced' to take part. I'm not intending to start doing so now. What's more, I don't think that CR as a game has ever done this either, so I don't imagine that they would either (even if it were possible for them to do so).
Secondly; we could make it a Tournament of the Gods, or a Tournament of the Guilds (as mentioned in the guilds forum). I personally feel that there's little difference between in terms of how the competition might work, it's just a theme either way. It could also be Law vs Neutral vs Chaos. (I personally think that many factions is more interesting than 3.)
Thirdly; in proposing to reboot this tournament there's been no mention of Classic Chaos format -
When making an unofficial tournament you simply have to choose a game mode as a default, otherwise you run the risk of having fixtures where players can't agree upon a particular mode.
I tend to choose Classic Chaos because I personally favour it, but it also has the advantage of putting all players on an equal footing (one player doesn't have more equipment than any other). I've usually set Classic Chaos as a default option, but included the caveat that players can switch modes if both wish to.
For the large part I don't think Law mode even existed when I was launching the majority of tournaments that I've created.
The proposal here is to set something up in an official capacity. As such it's viable to let it run across all game formats simultaneously.
Overall this is just a proposal, nothing is set in stone.
For match timings I'm proposing a rolling format because I feel that tournaments with an end point serve to 'end' player interest. We having nothing with this format, so it fills a niche - And not everyone likes the common 1 month competition.
For reward, there's nothing in game that can be offered that players don't already have, so a material reward in pointless for any competition. I'd propose instead that the reward here is bragging rights and/or a big shiny medal