I'll echo what's already been said.
Definitely don't want to use one smoothing group for the entire object. A good thing to remember is that every gradient you see on the lowpoly will appear in your normals and in this case, that would be bad.
As Philip has said, using additional edge loops on areas you want no gradient does a very nice job. Obviously this would probably put you above your budget so you simply add an edit poly modifier in your stack > add the extra loops where needed > bake > remove edit poly modifier > apply proper smoothing groups to lowres game model.
Here's what I would probably change (some have been said already):
- Make the front of the oven one face, the normals and AO should take care of the indents.
- Make the stove top one face, remove the bevels, use 6 sided cylinders (might not be enough) for the burners.
- Using planes that are alpha mapped might do the trick for the burner rails, as Twiz has suggested.
- The back piece that is above the top of the stove can also be a single face, the normals will catch that small bevel.
I'm assuming you're following a reference they gave you, correct?
