And to bring this back on topic.
My take has always been that Charted Space is far more than just the 3I and so I question things like:
Why the Aslan bother with the 3I and not just go Spinward?
I would guess that they do (both Rimward and Spinward). But the Aslan Hierate is not so much an Empire or Polity as it is a "Region" where Clan and "Pride" relationships tie groups together. Those who happen to find themselves born or otherwise "entrenched" on the Coretrailing edge of Hierate territory would find themselves surrounded on all sides by rivals - other Aslan who won't tolerate the "disrespect" of other male Aslan moving thru their territory just to (
supposedly) "get to the other side", or annoying Humans on the near edge of their holdings.
What are the Zhodani doing with the Thirz Empire that never gets mentioned?
The Spinward side of the Zhodani has several other smaller polities that seem much more suitable for assimilation than the 3I is.
Of course that gets back to the debate surrounding Zhodani motives . . . The official line being that they are "convincing" the (then: 4th - 7th Century) expansionistic Imperium to think twice about moving into its territorial claims and modifying their behavior along their rim-trailing border. So perhaps the Zhodani are not overly interested in assimilating those polities. Or maybe they already have - they are free polities that gladly wish to pursue their own independent policies that just happen to align with Zhodani priorities and concerns . . .
The Zhodani are generally written as being not overly interested in expansionism and consider their current Consulate to be about the maximum size that they would want to attempt to govern. Their curiosity and exploration however do seem to be highly focused along that Coreward corridor for some reason . . .
Or another way of saying:
There is a lot more going on in Charted Space to go explore and create your game in than just the 3I.
I think it is a pity that when Charted Space was initially mapped out, The Imperium was placed at the center surrounded, sort of like an Old World land empire. The Imperium either should have been left with one area as an open frontier of expansion/exploration, or alternatively, you could have all of the same polities as is, just move them (or just one or two of them) "outward" radially from the Imperium by several sectors so that they do not immediately abut one another. Still leaves room for intrigue and mystery, and expansion and exploration, with all of the old players.
BTW, on the original hand-drawn map of Charted Space (JPG included on the MT-CD from FFE), there is the Spinward border of what appears to be a rather large polity (minimum of about a sector in size, possibly much larger - it runs off the edge of the map), at the very trailing edge of the map bordering the Hive Federation in what is today called
Kolire Sector . . .
ADDENDUM: Another option (if you don't mind either a little math/geometry or a little handwaving . . . ) is to recognize that there are two additional (and eternally)
un-mapped directions in Charted Space:
North and
South of the mean-plane. They will never be overwritten by canon or third-party publishers, and a GM has a free hand to develop those frontiers. He just has to decide what mechanic he wants to use to represent and detail travel along those trajectories and how deep a "sector" is (and how many "
un-noted" stellar and interstellar bodies lie on the map in "empty" hexes because they are otherwise uninteresting, useless, or actual impediments . . . ). Jumpspace may in fact mean those "z-axis" trajectories are not simple linear projections anyway (meaning you don't need to be all that accurate with precise 3D mapping and/or angles relative to the Charted Space map). Your added sectors could be radial/polar-coordinate trajectory projections from Charted Space if you really wanted . . .
