Not many Olson 911s have the wheel so it will be interesting to hear how you like it with a wheel over a tiller. Ours has a tiller and for a 30 foot boat, is just fine. If I were to go to a wheel, I'd try to figure out how to fit a larger one as the one that ends up on the boat without any fiberglass work looks to prevent you from steering from the rail.
A benefit of the cockpit layout with the tiller and a decent extension, is the boat is very easy to singlehand. The angles work out just right where the main controls are just at the end of the tiller and with the extension, you can reach anything within the long cockpit.
Otherwise the boat looks to be in good shape. Ericson made several "versions" of the boat with various additional sail controls and various interior fit-outs. From the pictures, the boat seems to have the base level deck hardware and the higher level of cabinetry below. I haven't seen that many with the carpet hull liner, as most have Naugahyde that matches the headliner. I'm not sure which I'd prefer. I can't quite tell from the pictures if the boat is rigged for a spinnaker but that is a worthwhile addition if you are so inclined.
Oh, and make sure you do an out of water survey and take a look at the condition of the bottom and the rudder. Some of the boats have had blister problems that you'll want to get the price adjusted for if it's there.
Happy to answer any questions if they come up. We've had ours on the Chesapeake for several years now.