Rocky, it has been a while, but good to hear from you again. The power difference between the two should be of very little to no significance in real world operation and therefore shouldn't be of significance in the purchasing decision.
As to the features, probably you should study them carefully on the Onkyo site or at a dealer's site(e.g., Crutchfield)which lists them in detail. However, to name some significant differences: first, the 705 has the Audyssey MultEQ XT setup/equalizer rather than the 2EQ. This provides for up to eight measuring positions rather than two plus the center and also equalizes the sub, which the 2EQ doesn't. Both of these factors should lead to better equalization, especially in the low bass, where rooms typically need it most.
Others that could be mentioned would include three rather than two HDMI inputs and a full set of pre-outs. My view would be to go with the 705. As I also deal with estate planning and other financial matters in my practice, however, I'd certainly encourage building up that college fund as much as possible, most likely in a good equity mutual fund.
