I just bought a simple bluetooth receiver with a female audio output on it (cost 10 bucks new on ebay)...plugged that female output to the Cassette Adapter's male input in my car. Basically, this gave my car bluetooth with sound quality better then FM transmitters.
From there, I just setup a profile that activates upon connection to that specific bluetooth device. The profile does the following:
1. Opens my music App (Audiogalaxy)
2. Turns off my WiFi (since I'll be streaming my music via Audiogalaxy and traveling)
3. Begins playing whatever track was previously playing in Audiogalaxy
4. Sets a bunch of variables up all related to the fact that I'm in my car. These variables are related to having Tasker read outloud any incoming texts I get, jump to the next song by waving my hand over proximity sensor, and other stuff similar to that.
So uhh, yes....Tasker can that and plenty more. Pretty sure you could set it up to do things on voice command as well. You will likely have to do some research on that one...and you'll probably need to be clever in how you set it up to be battery efficient.