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GitHub User: simi
For repeatable content you can use refinerycms-copywriting. TinyMCE is garbage. It is better to provide few basic well styled styles like WYMEditor does in RefineryCMS. User can't destroy web with own content easily.
You can disable H1 in WYMEditor easily and force H1 into layout or page partial. You're free to do anything you want with HTML markup.
If basic pages are not enough for you, just generate own engine and customize. Everytime you're working with Refinery code, you're just using yours Rails skills. You don't need more knowledge. Everything is just a Rails engine.
Alchemy is pure CMS. Refinery is more framework than CMS. I'm customizing Refinery (backend and frontend) for each site I'm building. It is very easy to do with Refinery.
You can compare guides:
* plugin for Alchemy
* Refinery engine
The difference is significant. I'm not Alchemy hater. I'm just answering your questions. Feel free to join freenode#refinerycms, if you have another questions about Refinery.