I'm also looking for ways to teach Arabic to my future children (Dont have any yet
).
However, I think that whether or not you teach your kid letter sounds or words first has to do with what you aim to get out of it. My goal is for a multilingual child to also be multi-literate. I'm interested in my children learning, speaking and knowing MSA arabic and memorizing Quran.
These can be seperate pursuits. I have studied Quran since I was about 4 or 5 years old (I dont know much, but thats not the point) I am not a native Arabic speaker, but I study Quran and various Dua's on my own and I hope to get my kids in on the act from an early age. My goal for my children is conversational arabic. I learned to listen, learn and repeat my Quran and I learned a TINY bit of reading and writing in Arabic.
I remember reading on professional-mothering.com that she concluded that phonics was a poor method to teach any sort of reading to a child and that she'd wished she'd started more with whole word instruction, so I recommend you do a bit more research about teaching letters and sounds to babies. Its not that they cant learn them, but the problem comes when its time for them to combine the sounds in a meaningful way, and the fact that each letter has 3 forms further complicates some things so I'd think deeply about teaching letters and sounds FIRST to a baby under 3 years old if your goal is for them to be able to read Quran later.