IMHO there's no one-size-fits-all head regardless of the safety aspect.
Euro heads are a great thing to have on hand as they allow a lot of flexibility for shorter molding profiles, are very safe, the heads and knives are fairy inexpensive and the knives are thin enough you can grind/alter the profiles pretty easily. There are several companies making these heads but they work pretty much the same. If you do a variety of different work these are an item you won't know how you did without.
Corrugated heads allow for taller molding profiles and larger cuts in general. Knives are much thicker so require specialized grinders or outsourcing. These are plenty safe as long as the operator knows what they're doing. Again hard to imagine not having several of these on hand.
Insert heads are typically more specialized and use replaceable carbide inserts. Also, plenty safe…..in the right hands.
Heads that start to get a bit questionable are things like lock-edge knives. These heads allow more versatility than corrugated heads but require more diligence in operating. These can be used safely with an experienced operator.
Then there's smooth knives. These are held in a collar by friction alone and these are where many guys, including myself, get a bit squeamish. They've been used for a long time and can work well for certain tasks. But the tooling and collars need to be in nearly perfect condition and the person setting up really needs to know what they're doing. That's as far as my knowledge goes with these as I haven't used them so can't give any first hand feedback. Oh and I don't believe you can buy these new anywhere in the states anymore so you'd have to source them used.
that's about the extent of my knowledge….good luck,
JeffD