First off, you need to remember that
gene mods already exist in the Mass Effect universe, and did even before Earth discovered the Charon Relay; SA soldiers undergo genetic modification on a regular basis, and the wealthy have access to designer babies (though going superhuman, as was done by the father of the Lawsons, is illegal). This, frankly, is completely expected, since by that point the Human Genome Project is 160 years old and medical science is hugely advanced, even creating things like medi-gel that exist nowhere else in the galaxy. It's somewhat strange to say, but humanity seems to be one of the most advanced species in the galaxy, at least when it comes to the biological sciences. On one hand this seems really weird given how primitive and young we are as a species compared to the Salarians; on the other hand all the other species in ME seem to be far more genetically homogeneous, and don't suffer from the "easier" genetic disorders that humans fall prey to, so there was less of a need to develop those technologies in the first place.
What I'm getting at is that Revy's tech didn't create the field of gene modding; it was just an iterative improvement, combining the fields of nanotechnology and genetic modification, both of which are very mature in the ME universe. Quite frankly it's something that probably should have existed already, or certainly would in the next 50-100 years; it just required there be someone who had studied both fields well enough to combine them.
That´s true, but if you remember the numbers that we get from the guy in Noveria (in the side quest that we need to record a guys´s voice for an Asari) the upgrade % in all his offered products is between 8% and 16% of the initial capability (no one reaches the 20% threshold). That is the result of 160 years of continuous work in the genetic field of thousands of brilliant scientists. And we just created Captain America in 3 months.
Ok not exactly this, but you get my point.
Plus with the help of Mordin we just invented the means of modifying the whole biosphere of any world to make it suitable for colonization, also in 3 months.
And I'm sure that we are going to start the Eternal Youth relatively soon, and by the research points needed, we would probably get it in less than a year.
It's true that Revy didn't invent the science of genetic modding, but she has made it advance more than it could be considered to have any semblance of relative realism within the setting (If we are optimistic several centuries and a more conservative estimation would be a few millennia )this is like jumping from the Steam Engine to the Cold Fusion Reactor, or from the Crossbow to the Magnetic Accelerator Assault Rifle without any intermediate steps.
I´m only saying that most of the things Revy has achieved are not realistic or reasonable in any measure. She is such an impossible genius that she is both the incarnation Clarke´s third Law (
Any sufficiently advanced technology is indistinguishable from magic) and its inversion (
Any sufficiently analyzed magic is indistinguishable from science). She is basically a very stable Spark, that wouldn´t be out of place in
Girl Genius. Forgetting this, and discard lines of research because they are "unrealistic" (when our "superpower" is to break the limits of reality through science) would be like playing Dishonored with the challenge "
What A Weird Dream. Oh Well, I Guess It Was Nothing." (no magic power) funny but heavily limiting our potential options.
apart from that, I don´t really understand why to start the Mech investigation is less realistic that what we are doing right now, to me believing that investigating the Mech suit goes against the some established illusion of realism has no sense because we are breaking that illusion continuously, doing it once again it´s not going to matter so much. Especially with many of our tech tree options being much more "unrealistic" (phasing, orbital rings, planetary siege units...)
I´m not saying that we should initiate the Mecha Investigation right away, I´m just saying that it is probably going to be interesting (if it was not the GM wouldn´t have included it) and that after reading the whole quest I don´t see why starting that research path would be a treason against what has been done in the quest until now, as some people were saying.