Tell me some mods/upgrades!

I have a Neptune 4 Plus. I’m new to 3D printing. I want to know what has made your life easier when 3D printing, what are some mods/upgrades I can do to my machine?

I heard about silicone spacers, what size should I get?

Also will changing for a bigger nozzle help print faster or will it damage the quality of the print?

Any suggestions welcomed!