Hey Jon,
I'd encourage you to try out Knak. Knak is a SaaS based Marketo responsive template builder, built for Marketers. No coding required. It is similar to the other tools you mention.
Right now you can make fully responsive email templates, with no coding required. Landing pages are on our product roadmap, and will be launched by the end of May.
We have made 100's of templates for our clients at Revenue Pulse the 'old way', using designers and developers to create them for our clients. However, we believe that you should not need that middleman in the way. Marketers should be able to do this on their own, with no coding. We've created both tokenized and WYSIWYG responsive landing pages already. Now we're working to make this available to Knak clients as part of our tool.
Try it out. Your first template build is free:
www.knak.io
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