Let me play devil's advocate here.
Even if Cryptic publishes a chart that says 1 EDC = X Omega Marks, it tells us nothing. We still won't have any idea how many Omega Marks or any of the other requirements needed to get a piece of MACO gear.
Even today, months after Season 6 was released, no one knows what the cost of tier 5 starbase projects would be since Cryptic never released it and no one has a starbase of sufficient tier to even view the project costs. I am betting the same thing will happen for these Omega Fleet and Romulan personal projects. Chances are, we won't even find out that we're loosing out on the EDC/Borg Salvage conversion rate until a month or two down the road when people finally start unlocking the Mk XII gear projects.
So unless Cryptic publishes two charts, one with EDC/Salvage to Omega Marks conversion rate and another chart with complete cost requirements for each and every Omega Fleet project, I don't see how we'll know if we have been screwed.