I was raised on grass fed beef, so it's natural for me, and I never found it to be challenging. However I am also use to eating grass fed beef extra rare, almost like venison. IMO for most steaks, "rare" is already overcooked for grass fed. By extra rare I mean like seared tuna (steak is still raw and cold). This is how I eat grass fed beef when I'm in France:
To cook a steak like that, I would heat a pan on medium, not screaming hot, just reasonably hot. Put a bit of oil, don't let it smoke, place the steak in the pan for 30 seconds. Flip the steak and immediately add a pat of butter to the pan. Another 30 seconds and the steak is ready: plate and add a dab of cold butter on top. If the steak is really good, pepper is unnecessary and even salt is optional (I still like to sprinkle a few grains of fleur de sel before eating it).
For a cote de boeuf (large rib steak) I would make slits, insert garlic spikes or halved cloves, season with S&P this time, get a grill really hot (ideally charcoal or better, wood) and get a bit more cooking time, pushing it to "rare" - but never medium-rare which would be overcooked IMO. Something like this at the most:
Note that when cooking grain-fed beef I typically cook a bit longer and to higher temps, eating most steaks rare and rib steaks medium rare. I find that this is necessary to get the marbling in corn fed beef to melt, but grass fed has much less marbling and therefore cooks much faster.
Hope that helps.