I'm not sure if this helps but I've got a **** ton of interfaces as well. We created a policy report that goes out and looks at interfaces that have regex strings of "ip address" in them, and then looks for "no ip redirects". Same sort of thing you are looking for but you could do it with ip helper. So you could do the search of the config block starting with "interface" and end with ! , do a "Config file must contain" regex string "ip address" (this will find all your layer 3 interfaces in the config) and then you can also add another condition of config file must contain ip helper, if it does then create your remediation script to add in the ip helpers you want.
I really don't see this as an issue you can't tackle with the policy reporter. If you need more help or more details let me know, but again this seems do-able.