Trying to define an ideal EMR/EHR is like trying to define an ideal car. There ain't no such thing.
How do you go about buying a car?
If you are one of the few that don't have a favorite car to buy, you probably start with style - sedan, SUV, minivan. You look at crash ratings for safety, you look at price, maybe some more criteria. You narrow down to a few manufacturers and models. If you're in the market for family sedans, you probably have a short list: Ford Fusion, Honda Accord, Toyota Camry, Chevy Malibu, and a few more.
What do you do then? Do a little price check. Pretty soon you find they're in the same 'price range'.
Next, TEST DRIVE!
You may like one, your spouse may like another one. This is exactly how EMR/EHR buying works. You have to test drive.
Of course, you will must your colleagues, seek references, check reviews, blogs and so on, but you must 'test drive'. By this, what I mean is, see a demo. I suggest see two demos. After the first round of 'sales demos', pick the one you like best and ask for a detailed demo where you can ask pointed questions related to your practice, and try to see how this software will work in your environment.
If you now feel comfortable, that EMR/EHR is the one you go with.
Believe me, it is not as complicated as some people make it out to be.