That zig zig cardboard wouldnt allow crap for intake airflow.
I found a great way to block light leaks for fairly cheap and no obtrusive crap and ducts need to come off vents.
You can probly buy these filters cheaper if you know where they sell em wholesale, but depot was only $5, I went to home depot and bought a handful of filter replacements for your standard overhead stove range (air extractor for smoke and smells while your cooking) The fllters have 2 middle layers of black filter cloth and those sandwiched by layers of aluminum mesh material that is sturdy.
They come in sheets are various sizes for whatever stove you have, obviously you dont care about that but gives you options depending how big your tent flap recatangles are. I bought the 12" X 12" size since my intakes are 11X3 . I simply cut the filters into (3) 12" X 4" strips just bigger than my vents, it cuts easily with good scissors.
And attaching them is easy with these simple pins you get at the dollar store or any craft store for $2 for about 15. Simply put your filter in place where you want it over the tents mesh intake, push the pin through your filter and tent mesh, and snap the backer on the pin from inside the tent, secures it tight to the mesh. I did 6 of them per filter
edit - tried finding a picture of the pins but dont know what there called exactly, instead of a flag being on one side, the craft stores sell em with plane silver circles, with the backer pin the same as shown in this pic, to give you an idea what youre looking for
No light leaks, no ugly, flows plenty of air, fairly low cost, and I actually think the black sheets may be some sort of odour control like activiated carbon although its been so long I dont remember if the packaging said that
