Potential areas of concern:
- PCs will become more powerful relative to monsters. To keep things challenging, you will need to use more and bigger monsters; if you award XP by the book for monsters killed, this will cause your party to level up very quickly. You may wish to scale back XP awards, or use story awards instead.
- Depending on the items you hand out, many obstacles that would otherwise pose a challenge will be swept aside by brute magical force. Be aware of this when planning adventures.
- Without bonus spells for high stats, the 3E spell progression is stingier at low levels (but much more generous at high levels). So you will be reverting to the "linear fighter, quadratic wizard" model: The fighter starts strong and advances at a consistent pace, the wizard starts weak and becomes godlike. I would suggest consulting your players to be sure they're okay with this, and try to set your campaign in a level range that gives both classes some time in the sun.