I'd let that light ale go for more than 5 days on the cake. Let it go at least 14, then rack to a secondary or wait 21 days and go straight to keg/bottle. Then dump the stuck Three Crops on the cake.
If you're not going to use the starter up in the next few days, I'd chill it, decant some spent wort and add some fresh to liven it up before you use it for a beer. Wake those yeasties up!