Clothes Dryer lint has been a "cult classic" for a long time, and mixing the lint with melted parafin wax into paper egg cartons is an oldie. My experiments with clothes dryer lint are mixed.
Freshly peeled off the the screen, it takes a spark well (depending on the fabrics, of course). Matted down from being compressed and carried around in a plastic baggie or film cannister... varies. Aside from the question of exactly what the nature of the lint is, I think it's the short length of the fibers. It is difficult to "fluff up" the fibers to catch a spark. Sometimes it works; sometimes not. Contrast: I fire up a cotton ball (cotton wool) with a BSA HotSpark on the first try 99.99% of the time. I cannot remember the last time it took me two tries. "Aged" clothes dryer lint has not been as uniformly cooperative.
And it is slightly more difficult to ignite greased/oiled/waxed cotton wool than dry. When I teach folks to use a HotSpark, I get them to success first with a DRY cotton ball before I move them on to a petro jelly coated one. For me, greased lint is more difficult to light; YMMV.
To me, the value of dryer lint is in demonstrating how to use what may be at hand rather than as a prepared item - like grabbing some milkweed seed fuzz (explosive with a spark!)
As far as coating - anything that will burn with a wick works. Beeswax, SnoSeal, eye ointment, cooking oil - you name it.
Others have different experiences than me. But I'll point out that each "lot" of dryer lint is different.. and cotton balls are so cheap... draw your own conclusions. <shrug> if it works for you, have at it.
Tom