Honestly I haven't looked at many EMR systems from a psychologist's perspective. The EMR the psychologists I work with now is focused on College Health and would be complete overkill (and pricey) for an individual psychologist practioner.
I might suggest checking out
DoctorsPartner. I've implemented it in a doctor's office and been really happy with their offering. I can't think of anything that would be a problem for a psychologist. In fact, they offer free limited customization, which no other EMR I've found does. I think this type of customization might work well for a psychologist that doesn't want to use the SOAP format of documentation that so many EMRs require.
Do you do a full 5 axis diagnosis? I'd be interested to know if DoctorsPartner could support it with the customizations. I may send them an email to find out.
I also like DoctorsPartner because they offer unlimited free online training. That means they have to build an easy to use product so you aren't calling them all the time. Oh yeah, and the price is good too. It's a monthly fee which should match well with the way you generate revenue. Man I should sign up to be their salesperson.
I'd love to see your thoughts if you do a demo on how it would fit for a psychologist.