This probably isn't the right forum for expressing this thought, but here goes anyway:
What exactly is the freedom that Yesod takes away from you? I know this idea gets passed around a lot: Yesod isn't "really" Haskell, Yesod is its own language, etc. But all of that is really just talking about some sugar that Yesod puts in place for you: under the surface, it's just functions, data types and type classes. You can go ahead and write a complete Yesod application without using Template Haskell of QuasiQuotation.
So what's the restriction that Yesod has that Happstack/Snap don't? Yesod requires you to provide some datatypes. That's it. What's the purpose of the datatypes? Mostly, it's about type-safe URLs. I'm not exactly sure why the term "restriction" or "freedom" even applies here: Yesod has a *feature* that Happstack/Snap do not include out of the box.
Let me phrase this in a different way: "But I don't like Haskell, because the idea of Python in more interesting for me. Python gives you some freedom." I really do see this as the same argument. You can go ahead and right some code without static type checking in Python, and you might even write it faster than you would have in Haskell. But go ahead and start making changes, and unless you have some very good unit tests, you're in for a world of hurt. In Haskell, often times the compiler will save you from yourself.
The same is true in Yesod. I've refactored incredibly large codebases, with hundreds of different resource patterns, and *never* had to worry about 404s. Maybe some people consider that giving up freedom. I consider it giving up the freedom to shoot yourself in the foot.
Oh, and if you are absolutely dependent on the idea of getting rid of this data-type requirements, and want all the freedom of dynamic routes, you can try out a 44 line module[1] that I mentioned recently[2].
OK, enough of this rant. I'm not trying to attack you, I'm just tired of this notion that Yesod is a ball-and-chain around your ankles. People can have legitimate reasons to prefer Happstack or Snap to Yesod, I've never claimed that it was a perfect framework for everyone. I just don't think this is one of those legitimate reasons.
Michael