honestly no its not worth it
eldritch blast on a non warlock isn't that great
magic missile = 100% hit and that stacks with a certian item to out class the Hex \ scorching ray combo when you consider scorching ray still has to roll for hit so ShadowHeart pops a blot [advantage to next attack] and shooting from high ground is important
+ of course there is already a warlock so unless you want to solo its just better to take 2 points of char, with the volo item and 17 start that's 20 [+5]
its your game, have fun guys