The objectives would be player-deployed, as part of the process to begin holding sov in that system. Already we have two major 'objectives', the TCU and I-Hubs. Perhaps these should be switched to a timer-based approach, thereby alleviating the grind of structure-shooting presently in place.
Important to note: hostile structures like Blockade units could still be required to make the targeting of these objectives possible. This allows defense of systems viable, as it gives several hours of prior notice to the sov holders an attack is taking place. However, once blockade units are successfully onlined, there shouldn't be a massive penalty to the attacker to grind through several hours of shooting structures, waiting for more timers, then more shooting structures.
In hindsight, the changes I've suggested are actually very minimal, replacing unnecessary shooting with timer-based captures of facilities. However, that is still extremely important. Wheras previously a hundred or so pilots would be needed to gank an Ihub, now only 5 or so would be needed, a few people to deploy the blockade units, and a few to camp the TCU and Ihub. People that don't bother to defend their territory would pay the price.