Thanks for the the replies, everyone! Helpful to see other people thinking the same as me.

I'm applying for what looks like a great PhD position to do with sustainable food consumption. It's a project that has received several million euro in funding for a group of academics to undertake and they're advertising a funded position for a PhD to join the project. All parts of it seem to be planned out, so I'd be just doing as I'm told for 4 years.
However, the range of studies involved, the skills I'll have at the end, and the area of research are so good that I feel like it's worth the lack of freedom.
What are your opinions on these sorts of positions? Will I be more employable having been attached to a real research group?
Thanks!