Opinion: will you be reluctant or eager to switch from 5E to 6E?

[PhoenixPhyre]

Concur. The mechanic is fine but it's being applied far too widely at present.

I wouldn't say far too widely, but improperly. There are some spells that should absolutely require it that don't (eg forcecage) and some that shouldn't require it (eg barkskin). Personally, I think that concentration is simultaneously too easy to break (for monsters, but this is minor since so few actually use it) and too hard to break (for more optimized PCs).

But forcecage needs a rethink IMO anyway. It's anti-fun.