First thing, relax. Drink a cup of coffee, a beer, or whatever and just chill.
Done that? Ok, here's the thing. I've been around plenty of kids that were almost totally unintelligable at 3 years who still turned out just fine. They might still be somewhat inarticulate, but if current situations continue that might be a qualification for president. Regardless they're still plenty smart, just a little mush-mouthed.
As an aside, I had a great vocab for my age as a kid. I would always enunciate with near perfection. My aunt was a speach pathologist. Her daughter was the most mush-mouthed, hard to understand kid I've ever seen. Drove my aunt nuts. Shoemakers kids go barefoot and all that. But, that girl is now getting a PhD in physics at Stanford.
For a 17 month old to have 25-30 clear words in their vocab is actually doing rather well, or at least average. If your doctor is freaking beacuse she can understand you, but you can't understand her then you need another doctor. You certainly don't need a team of "experts" to watch your interactions at this point. If she hits 2 and still showing no improvement then I would be concerned.
If you're still worried then the thing to do is talk to your doctor (or better yet a new doctor) and try to find out what the causes of delayed language development happen to be. Then see if any of those issues apply to your daughter. If one or more do apply then you can take action based on those findings. If none of them do, then your kid is simply to the left of the middle of the bell curve on that specific developmental milestone. Not a bad thing, just the way it sometimes turns out.
If you kid is just a little a slow on language development, then doing things like talking to her in very clear voices, reading to her, and working with her to prompt clear words is the place I would start. You probably know what some of the babble means (e.g. my 2 year old daughter calls her toy crocodile a "dyko") so when she says certain things you can repeat the correct word back to her.
I'm sure there's books that deal with that issue that can give you better advise than I can.
Good luck.