By reading your post I would say:
1. You havent convinced yourself on actually getting an AR.
2. You sound as if you are settling because of price.
3. If #2 is correct check out Del-Ton AR's, they are about that price range and have all those features you say you dont need.
4. It is a little more expensive than a Del-Ton or a Palmetto Armory but I just picked up a Windham Weaponry M4 clone and at aboit 150 more dollars it is about 800 more dollars worth of gun. I know you said you didnt want to spend more, but why be cheap on something like this.
5. If you feel like you really dont have a need for it, use that $700 to get some other things you may have a need for. I am a firm believer in not having firearms that I have no need for. All of mine serve at least 1 real world purpose.
The forward assist is a great feature, you dont need it till you need it.
The chrome lined barrel is nice but not needed
The dust cover IMO is the most important feature of these three you listed, in the long run you will be glad you have it, or wishing that you did.
Just my .02