While not so much direct ideas, I do think it'd be interesting to see some NRP ideas that break away from archetypical ideas. Not to say that space opera / fantasy / steampunk / apocalypse / colonial aren't fun (i've been in... like, most of your NRPs in some capacity over the years), but I think you could perhaps garner a little more giddy enthusiasm from new and old players alike if things were mixed up in some way, you know?
I'm not saying 'do this' or 'do that', of course, but the very nature of NRP allows not necessarily just 'nations' but also any group large enough to differentiate themselves as factions or controlling powers.
Maybe instead of, for example, in Adruis, instead of playing standard nations, we were to play multiple pirate factions within one nation? I think it'd be pretty sweet if in The Final Frontier, instead of full nations doing generic nation things, it was a selection of expeditionary / corporate forces waging political and economic warfare over a single, highly detailed and described planet. Just things like that, just little additions and changes which would make the idea seem a little more fresh, you know?
:)