Jesus which part of GTA are you in so I can stay the **** away.
As far as advice/suggestion goes, I think the cop was probably having a bad day and went to town with you. Also in the GTA having ANY sort of cover ANY part of the license plate ( not including the stickers ) is illegal. Like others have said, most cops don't bat an eye on the covers but it's something they can nail you for.
As for the license plate, you're SoL on that one, it's an auto write up for the cop. Move to Quebec if you don't want front lic plates.
I'm totally speculating here but, I think he might have seen a note for the week before in their database. The summon he gave you is basically an ultimatum for you to fix everything and prove it to the crown, sucks that he also threw in tint and cover.
imho, don't give them any reason to pull you over in the first place and you'll save yourself a lot of headache!