You aren’t doubling your spell pool though as you still have the same number spell slots a day, you are going to miss on a feat, and your offensive spells will suck.
And you can prepare spells as a wizzard based on your modifier meaning at 10 INT you can only have one spell from the wizard pool, at 12- 2 spells etc.
So you either Gona Gimp your main spell cast attribute or you will have to have a very limited use of the wizard spells.
I often dip 1 lvl wizzard on some builds but that usually just to get Haste or Shield, really the usefulness is rather limited.
I mean as a cleric you are potentially losing your 3rd feat which could be War Caster or Alert or max your Wisdom and in exchange you get Haste and some other utility spell as you won’t really be able to do much with offensive wizard spells.
The trade off seems balanced enough. And let’s not forget you can craft or buy haste potions so in Min/ max situation you are still better off full cleric
