The Fall of Gondolin

by J.R.R. Tolkien

but he carried an axe rather than a sword, and this in the speech of the Gondothlim he named Dramborleg, for its buffet stunned and its edge clove all armour.

What came of it?

There were those of the Tree, and they were a great house, and their raiment was green. They fought with iron-studded clubs or with slings, and their lord Galdor was held the most valiant of all the Gondothlim save Turgon alone.

Slings do appear in JRRT's writings in the hands of heroes, though whether this is canon or not is a subjective question.

Already the half had passed the perilous way and the falls of Thorn Sir, when that Balrog that was with the rearward foe leapt with great might on certain lofty rocks that stood into the path on the left side upon the lip of the chasm, and thence with a leap of fury he was past Glorfindel’s men and among the women and the sick in front, lashing with his whip of flame.

Seems pretty clear that at this point in JRRT's envisioning of Balrogs, they don't have wings since they have to leap up to a higher stone.

He is to bid Turgon to prepare for battle with Morgoth; for Ylmir will turn the hearts of the Valar to forgive the Gnomes and send them succour. If Turgon will do this, the battle will be terrible, but the race of Orcs will perish, and will not in after ages trouble Elves and Men.

In this version, Turgon's stubbornness didn't only doom Gondolin, it lost a chance to eliminate the race of Orcs entirely from Middle-earth!

‘As for me, I am of the Noldor, and long must be the hunger and cold the winter that shall slay the kin of those who passed the Grinding Ice. Yet how think you that we could labour countless days in the salt wastes of the sea? Or have you not heard of the waybread of the Elves?

One of the later writings seems to suggest Noldor can starve to death.