Some interesting ideas - I like the idea of posting screenshots. I'm expecting reports every two days of real life, so including a screenshot in them would be nice.

I'm starting to cool off on the 2 day advance warning thing - the problem is that, with the possibility of other players fighting some battles, the incumbent can't actually control or predict how long it will take to play his reign. It depends on how quickly other senators answer the call if their avatars get into a fight. So a 2 day warning just means adding an extra 2 day hiatus in the middle of a reign.

Instead, how about:
(a) report every 2 days (minimum - one-liner; ideally a screenshot; everything else is icing on the cake)
(b) pauses after 10 turns & produces mid-term report (reasonably detailed)
(c) mid-term Session: two days for Senators to debate and draft emergency motions & one day voting
(d) player continues & we're back to (a)

Ideally, I'd be hoping a 20 year reign would span 2 weekends (with the incumbent trying to blast through 10 turns in each weekend), with a mid-term Senate imbetween.

Then we'd have a full Senate session lasting 5 weekdays, ending with a Friday election and on we go.

In the early game, we might be covering 5 years every two weeks.

Is that an acceptable pace?

I think it's actually the full Senate sessions - rather than the mid-terms - that will slow things down. But a slower pace is a price worth paying to get all 19 of us Senators involved in this PBM at the same time.