Renegade Reinterpretations
Relations: Krogan
"The same? No, it's not the same Shepard. The Krogan fought the Council, and then kept fighting for pride and for honor and ego until there were almost none of us left to fight. You Humans, or at least your leaders, had the sense to stop fighting a meaningless war you could not win before it could destroy you. That is the difference between our species. That is why Humans are feared for what you can still do and the Krogan now pitied for being too stupid to recover. Do not compare your species with the fate of the Krogan."
-Urdnot Wrex
As there is no unified Krogan government, there are no diplomatic ties between the Alliance and the Krogan as a whole. There are, however, a plethora of ties of various sorts with the many warring tribes and chiefdoms, particularly on the Terminus Frontier. Despite shared sentiment against the Turian Hierarchy and the Council in general, however, any Human expecting an instant comraderie will be quickly disappointed and even the most militantly anti-Council Human politicians find it hard to admire the Krogan. The tribes, gangs, and petty warlords in the Terminus are as happy to target Human colonies as any other, and as willing to be paid by the Free Hegemony to fight against the Alliance as vice versa. Or perhaps not not equally: many a Krogan see more honor to be won in fighting the reputation of the Humans than the Free hegemony.
With a lack of unity preventing any single political relation, common cultural views are the next best alternative. The Alliance has quickly learned what the rest of the galaxy has known for millenia: Krogan are tough, Krogan are better divided than unified, and Krogan are unreasonably aggressive even by Human standards. An immediate post-Second Contact War sentiment that anyone opposed to the Council must have some redeeming feature has long since passed: the Krogan's well-deserved reputations for casual violence has only added their species into the xeno-phobic fears of the Alliance. While Terra Firma politicians will be the first to elevate the Krogan as proof as to what the Council is willing to do to others, it is matched by the frank admission that had the Alliance been in the same positionas the Council in the Krogan Rebellions, Humans would have likely done worse to the Krogan. Keeping the Krogans from unifying under a new warlord is one policy that both the Alliance and the Council are in perfect agreement over.
If this disappoints any Krogan, few show any signs. For their part, Krogan view Humans as they do most species: another alien to fight, and all the more enjoyable because of Humanity's reputation. There is no sentiment of common cause amongst the Krogan: those who don't deride the Alliance for relying on orbital bombardments rather than ground fighting against the Hegemony will often mock Humans for ending the war and submitting to the Armistice. Humans are not the spiritual brethren of the Krogan: the Krogan were beaten, but never submitted, whereas the they see the Alliance as the opposite. Still, many Krogan chieftens are willing to overlook Human flaws in favor of Human credits: it is an open secret in the Terminus that the Alliance not only buys off many Krogan gangs from attacking Human colonies, but pays them to attack the Free Hegemony instead... even if using proxies is just one more proof to many Krogans that Humans don't have the quads.
As it applies to the trilogy...
In a Xenonationalist galaxy, the Alliance treats the unifying Krogan of Wrex or Wreave with significant suspicion, enforcing the Krogan DMZ with the rest of the Council and continuing the policies of letting the Krogan either reform or die. Wrex is viewed with extreme caution from a distance: Wreave is seen as the harbinger of the next Krogan Rebellions. Council members with more experience with the Krogan than Humanity caution against any interventions, and the xeno-nationalist Humanity isn't inclined towards such anyways.
In an Assimilation galaxy the Alliance-controlled Council begins making noises of re-incorporating a unified Krogan into Citadel space, with the intent of using them to stabilize the Krogan bnds in the Terminus. Wrex's ties to the Council are more of a hinderance than not, because blatant alien support and aid is a political liability he could do without. Wreave is far more oportunistic and cooperative, gleefully using Human support to wipe out his rivals in exchange for destroying the Krogan bands that target the Alliance, a relationship of empowerment that many alien observors fear will blow up in the Alliance's face at galactic cost.
Author Note:
Any Human who goes up to a Krogan in a bar expecting anti-Council kinship mixed with pro-Human respect is likely to wake up with notably fewer teeth, if they wake up all. Coroners in Krogan space will list such encounters as 'death by stupidity' rather than murder, sort of way that a Human going alone into the ghettos of Khar'shan is a victim of suicide.
A reinterpretation of the Krogan in this universe is that Krogan space is one of the many frontiers with the Terminus. Besides Tuchanka and their colony worlds, the Krogan are notable as traveling gangs of pirates, slavers, mercenaries and whatever else which constantly travel the Terminus like, well, gypsy caravans open for hire to fight whoever the bidder wants. Krogan aren't just stuck on their rocks: there are still considerable numbers of groups and ships, left over from the Krogan Rebellions, wandering Terminus space beyond the Council's reach. Every once in awhile, a Krogan Warlord will rise and begin to unite not only the Krogan colonies but this nascant Krogan armada divided across the Terminus.
And then someone, usually a Spectre, kills the Warlord and sets the clock back once again. Wrex or Wreave may well be the first Warlord in four hundred years, and what everyone fears is that either of them will unify the Krogan in a galactic waargh and- I'm sorry, new Krogan Empire and be ready to war against the galaxy.
(But seriously: Warhammer 40k fans? You haven't even seen the outlines of 'Masshammer 4k: Where there is only War (With Krogan)'.)