I do the big starter with fresh yeast and save half of it for the next brew, at which time I split it in half again. Less to store, no hop or break in the yeast, and easy as it is part of the process.
I also add a little more grain to the mash tun each time, and after I drain, add a gallon or so of water. Right before I get ready to clean it (during the boil), I drain it into a gallon jug. This gives me all the wort I need for the next starter. I like doing things "in process" so there are no additional steps I have to do outside the brew prep or brew day. Also keeps me from forgetting something and then needing to run to the LHBS in the 11th hour in a panic. Though, I am sure I am the only one that ever has that happen to him...
I think most of the issues with yeast come with scale. Yeast in a giant conical are under huge stress from all the weight on top of them and whatnot. We don't see those issues brewing 5-10 gallons at a time. I have used the same yeast for over 3 years and not detected any change in character. YMMV...