OP_IF to allow multiple choice release and hash protection would be nice to have operations.
Yeah, it feels like there should be some patterns that you could reasonably convincingly argue don't have any additional DoS risk when used in P2SH.
For instance, if you're doing these branching transactions, like:
OP_IF
some existing standard thing
OP_ELSE
some other existing standard thing
OP_ENDIF
...you're doing a single true/false test then immediately throwing away everything except the content of one or other branch, leaving something you can already do as standard.