4. Deb Lives
Instead of Deb being the only casualty of the finale, she should have been the lone survivor of the attack I mentioned. They could've used Deb to properly call back to elements introduced in recent seasons that were all but completely abandoned in this season. She has known Dexter's secret for two seasons now and kept it all to herself, not to mention she was grappling with being in love with him prior to that. Dexter and Deb's complicated relationship has been at the core of the show from the start. And although Deb killed LeGuerta and saved Dexter at the end of the seventh season, she never lost her humanity or her role as the moral compass of the show. I would've liked to have seen her return to being a dedicated homicide detective sooner, torn between knowing what's right and her love for Dexter. But by the finale she would've fulfilled her ultimate destiny: to bring her brother to justice.