If I put my DM houseruling hat on I'd do something like this:
Wiz3/Cle2
Standard multiclassing rules for slots available 4/3/2
Because highest slot is 3 and highest spell known of 2 is less than 3, character gets a bonus highest level wizard spell known of 2+1=3 and cleric of 1+1=2.
So Wiz3/Cle2 still gets 4/3/2 slots,
but knows 11 wizard spells (8 must be level 1, 2 can be level 2, 1 can be level 3), and all level 1 cleric spells plus one level 2.
Would this outshine a Wiz5? Maybe.
The multiclass gets more dialogue options, more cantrips, some weapon/armour proficiencies, better HPs. The Wiz5 gets more level 2 and 3 spells known, better arcane recovery, an ASI, and only needs high Int.
