[Saurreg]

If Feanor had survived his encounter with Gothmog and his balrogs, he would only be hastening the defeat of the Noldor on middle earth.

Without the death of Feanor, repentful Maedhros would not have been in powerful of the lesser host of the eldar and I do not think Fingolfin would be that willing to seek reconciliation. It would be far easier for the Enemy to struck at the elves, at each divided host than to attack one united people.

I wonder if Feanor had lived, would he come into armed conflict with Thingol?