For example, I'm guessing that you only need your level text to update when you change levels. So instead of updating it every tick like you are now, just change it when your level changes. The same with the level score (time). Currently you're updating it every tick, but you could just update it every second instead and it would be much more performance friendly. Those are both from the Level_1_world sheet.
Also on the Main event sheet you are saving to webstorage every tick. Is there a way that you can set that up differently (In other words, does it really need to update every tick)?