Lukewarm on Marketo - Powerful but really complex

Complexity - because there is SO much available in Marketo, it is extremely complex and very difficult to learn. They onboard you with a week of required training which 1) is hard to make time for (unless you have/are a dedicated resource that ONLY does Marketo) and 2) actually isn't enough time to get through it all (and we have the basic version). It's also challenging to figure out where to go if you have a question. You'll have an implementation consultant (plus one for any additional modules you get), plus your sales rep, plus their e-mail based support process and then there is their crowdsourced support community... so you do a lot of searching for info, might ask support directly but the net result is there is a whole ton of info out there but aren't many easy answers to basic questions. Admittedly I am part of the problem. I am not a 100% dedicated to using/learning Marketo, but isn't marketing automation supposed to automate and simplify complexity rather than introduce more?

Really Bad UI - They have done a lot to try and simplify and modernize Marketo's interfaces but the excessive complexity and all the available options means the UI is littered with so many elements that it's hard to know what to do, what's required, whats optional, if you are doing things right, etc. My needs are fairly basic and will become more complex over time, and their UI should be boiled down into the most basic steps for the most common use cases. I'm flying a quadcopter... I don't need NASA to do it.

Templates need work - many of the templates provided by Marketo are really dated looking. It would be great if they could provide a library of easy to import/use templates that are mobile adaptive out of the box.

Cost... and not just price: First of all, Marketo isn't cheap (although it's far from the most expensive) so because it will take a while to ramp up and build ROI. We've had Marketo for 6 months now, and we are getting a bit more value out of it than we were from a $50/month mail service (but we are paying a heck of a lot more than that for Marketo).