Considering the sale ended 12 days ago, I feel like it would be unfair to everyone that has bought it in the meantime if I made a temporary discount just for you, even if you happen to be one of my most loyal customers. The monster collector engine release sale also lasted 1 week, instead of just 3 days which I usually use for release sales. There will be more Itchio sales, and I always join in when there is one, so just check back regularly and chances are you'll catch the next sale. (Itchio sends out e-mail notifications if you've got those turned on - I think it's possible to turn it up to max to get notifications whenever anyone you follow posts a new project, sale or a devlog on top of just the big site-wide announcements, too... if you do that, you'll never miss a sale again!)
You should also probably take some time to actually make a game with all those engines you bought too... Making 5 games at once tends to get pretty exhausting. :P