I don't think the criteria for a CMS is that it does these things well
I agree, but the criteria for a CMS is not that it does a few things that look like a CMS, either. My car has seats, but this does not make it my leaving room
I agree with Dan Stevens that your best bet is to find an agency - or a self-service provider because the Marketo-provided templates are not tested often do not pass the test of display compatibility with different email platforms. I have a designer I always use when my clients need email templates built - in part because she tests all her templates in Litmus. It sounds like Joe Reitz has some good referrals too. You need someone who knows Marketo as well as email design and development.