A coffin! Cobwebs, maybe a skeleton head. A Christmas tree in storage, maybe an old bedframe (No mattress), old stuff, maybe that old clock add on, make some Coca-Cola prints that are retro like they are "Signs" and are just stacked up, old books, a treasure map (AS SEEN IN THE GOONIES!)
Holy crap
The Goonies is a great movie to watch for random stuff to go into an attic.
Also! Dead plants/ pots with just old sticks in it basically. More: Old Radio/ Phonograph. STACKS OF RECORDS! Also, the lantern add on, and as stated above, an old chest of some sort.