I also use paper next action lists in my day planner and loath to re-write them every time. My solution was to use a highlighter to cross off completed actions, leaving uncompleted ones blank. This way the uncompleted ones really jump out at you and you don't loose them amongst a sea of check marks and crossed off lists. Here is a screen shot:
Then during my weekly review I get to sniff my highlighter while I scratch stuff off. When a page is completely highlighted on both sides I can remove it. Having one or two lone actions left uncompleted serves as a reminder that they are overdue and need to either be re-thought or completed.
You're doing exactly the same thing as me! I'm glad to see it works for someone else.