Hello,
Maybe this could be done by adding a special building called a "MIRV AutoLaunch Center" where you can input the MIRV targeter items into its inventory and it would consume them to launch MIRVs in a defined range around it at biter bases. So you can automate launching MIRV and loading targeter into the building and strategically position the building where you want to interdict biter bases with MIRVs.
Not as overpowered as the Ion Canon mod as it consume lot's of ressources to build consumable MIRVs and get targetters, it would be limited in range by where you put thoses building and it involves logistics to bring MIRV targetters on top of adding a heavy cost if you want to maintain multiple buildings to cover a large area.
Not sure how hard this would be to mod, just an idea!