Sorry, did I miss something?Yes, intrigueing it is.
I can't comment intelligently on the Diet, but the HRE system had (has?) a tremendous amount of sophistication to it: the Electors, the Reichsvikarien/King/Emperor system for ruling, the electoral capitulation the king and emperor agreed to before assuming power, etc. Lots to play with as far as game mechanics, and lots to balance just as with the Senate.
More broadly, I would say three things:
1) A good discussion of game mechanics need not lead to complexity. However, I think the senate-style PBEM has a load of unexplored possibilities. Since we're not starting for a few weeks, we may have a great chance to carve out a design for this round.
2) The unexplored possibilities I'm most interested in are in the case where someone besides the Head-of-State (whoever that turns out to be) takes control of the campaign on a periodic basis -- not to do whatever he/she wishes, but instead to take care of specific segments of the campaign: economic activity, agent activity, etc. For example, what if, even though the Pope has nothing to do with the HRE itself, the HRE's religious affairs were controlled by someone playing the Pope? I'm not particularly stuck on that idea, I just give it as an example of what I'm talking about.
3) It took me a little while, even though the WoS is quite simple, to understand where and how I could contribute. Whatever we decide, I would very much like a straightforward document describing the function and duties of each position (or class of positions). It would go a long way toward bringing more people into the game.
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