I also dislike baby talking to small children. I don't think it encourages speech or vocabulary, but I'm not big on pronunciation, mainly because language is for communication and if I understand the child then the word has served it's purpose. Having said that i cringe when older (3-5) kids ask for things via baby talk; thier dee-duh (dummy) or dri (drink)..
With DD2 we do use both 'her words' and normal words. Though most of her words are phasing out now she uses the proper names.
I think proper pronunciation will come with time and oral motor skills. My DS4 is a good example his vocab is huge but he can not say the sounds 'th', 'l' or 'r', lolly is woh-wee, he is a perfectionist and is noticing his inability to say these sounds (he asks me to spell them out to him). No amount of saying the right words to him have made any difference...
I do sometimes say yes and repeat the word but only when it is really off. But i'm really aware of his self-esteem on this issue.
Other math things to do....
If she knows shapes, has she been exposed to 3D shapes? the first, next ans last is a math concept (i think), how about having number cards with a 1 2 3 on them and asking her to order them? DS loved that game, it works for bigger numbers too.
