Personally, I wouldn’t worry too much about being off site in such a scenario. In fact, having EMH in all the parks can actually benefit off-siters potentially. The on-site “rope drop” crowd (which is already a subset of the total on-site guests) is now split between 3 parks instead of just 1. This means the overall impact on off-site guests is minimal. Of course, it will be higher than, say, going to a park that does NOT have EMH. Maybe.
We’ve always tried to Rope Drop the parks as off-site guests. But for us, we are not the type to get there like an hour before rope-drop. Because all that means is we’re spending an hour in line outside the park so to avoid waiting a little extra time in line INSIDE the park. If we’re going to wait either way, I’d much rather do it with as little waiting outside the park (well, I’m calling being contained behind the rope “outside the park” even though it technically isn’t) as possible.