Normally I don't even use fireball, but in that fight, the ones I had available didn't really seem like good ideas. Slow can only catch 6 foes, Confusion was too small of an area, etc.. Plus I couldn't be sure I could avoid damage to keep concentration going for very long- in addition to all the Wights, some of whom had longbows, the DM was throwing 20's like mad, and there was choking smoke that you had to make a Con save against at the start of each turn or take necrotic damage that lowered you maximum hit points.
A lot of people crow about how great fireball it is (or gripe that it does too much damage). I don't know, my experience has been that it takes multiple fireballs to really make an impact, as mooks have a lot of hit points to chew through, fire resistance or immunity isn't super uncommon, and friendly fire isn't.
If I wasn't pretty sure I need a break from playing a full caster, I might be tempted to play an Evocation Wizard. The idea of just dropping Fireball on top of the melee while they're surrounded by enemies does sound like a lot of fun, lol.