Alright, lets analyze my current favorite build - Fisher King into Super Juggernaut Undead Chimera into Companions of the King. First, lets see what these abilities offer us:
- FK: we finally get to finish this, meaning that we are not floating 12 Arete anymore. We gain alternative Decimator Mitigation, upgrade Hunger Sated, gain 50% Rank Gain and 10 Accursed Favor
- SJUC: We gain 1.4(or 1.5) Rank, 2x(or 1x) 100% to stat of our choice and we open up another Defining Advancement slot
- CotK: We get our companions to our Rank, up to 50% to all stats, up to 100% to Rank gain, we can be resurrected by our allies
Pretty decent spread of utility and combat power. SJUC, in particular, would vastly increase our general combat power(Combat Rank 10.2-11.6, Blood Rank 11.2-12.6) as well as utility via Blood. In general, we likely want to get FK and SJUC now, as both should help with Decimator, and then get CotK when we have opportunity to do so. CotK does have additional requirements we currently don't know, so that might prove to be an issue.
When completed, this should give us some major boons. With FK and CotK we'd be at nutty 250% Rank Gain(as an example, that would turn 0.2 Rank into 0.7 Rank) and, more importantly, this would put all our friends at Rank 9.6(or 9.7). Other than absolute improvement in their combat ability, this should have additional utility for Letrizia(due to Sharpbright) and Gisena(improving her research speed). Additionally, this should unlock Shrouds for Gisena, Letrizia, Aobaru and Aeire, which will obviously bring even more utility to the table.
Finally, don't forget that Orb gives us 0.125 Rank, which turns into 0.44 with 250% Rank Gain. This would be enough to push our Rank past 10, allowing us to add Adorie to our Companion list.
So yeah, this sounds pretty good. I'm sure that it's not as strong as SitS/OaF3, but it does make our companions much more relevant, which is what majority seems to care a lot. Build up is good, and there's a lot of value here.