I'd be willing to forgive Edu and Arteta for only bringing in one striker this summer if they settle everyone's contracts and the forward they bring in is a game-changer who enables greater scoring potential across the front six.
But I don't think any internal solution for backup should be Lacazette. Converting Martinelli or Smith-Rowe into a false nine, recalling Balogun if he's any good, or taking a punt on an unheralded young striker would be preferable.