The ability to easily embed forms into our site using tools like Zapier is great! I wish there were more integrations with other platforms/apps, but it's still pretty easy for us to build custom form fields or add in additional sign-ups when needed.
Not much that we dislike at this time - however, integration issues are probably my biggest issue so far. We're building out an internal tooling system which will be integrated within each department across 3 sites. Each person who signs up has their own individual needs / goals they'd want help achieving through these services, thus creating multiple forms for them instead of just 1 master one.