A simpler way might be to have a rating based on points from the last season plus this season and average. So if you ended the last season at 1200 points you start the next season rated at 1100 points(ave of 1200 and 1000). Or it could be prorated by how many months into the new season. So during the 1st month say 75% of last seasons ranking plus 25% of the current months. After 2 months in that might be 3/5 of the last season and 2/5 of the current and so on.
If you delay games you will not really improve your standing for the next season. And going for wins against lesser opponents also will earn fewer points as their rating will be lower at seasons start.