I think with the proliferation and effectiveness of countermeasures passive target acquisition and first shot accuracy with traditional ballistic methods might be a better place to focus but I understand that's very hard to do nonprofessionally as an individual thanks to the rules and laws.
On the other hand, there is a lot to be said for making them blow their $1k active countermeasures on your $500 missiles before sending a real one in to finish the job. Heck, even just forcing your adversary to treat every sky like it's hostile is worth a lot.
Both approaches are clearly worthy of development.