I've been tossing around the idea of starting a group of people who are committed to buying Bitcoin every month. Can be a small portion, like 5$, or however much people can afford (I suppose it would make sense to use higher amounts for fee reasons, though). I myself have set up a monthly wire transfer from my bank account to Coinbase and a recurring purchase of Bitcoin every 1st day of the month. This is really simple, and you keep investing and $-cost-averaging your BTC purchases.
Who's in?
The thing is that $5 is a pretty minute amount as that means $60 an year which really is considerably low if you even consider the various fees exchanges charge even coinbase has also been known for charging high fees. I think the strategy which you are saying is good but the problem here is execution. Averaging is really good but if you are thinking of something which has a great life over larger term of 20-30 years but I think bitcoin is still not that much mature.