You are seeing the car attempt to bring the O2 into line, it will add or remove fuel to get the signal it is looking for.
When in closed loop the ECU has control over a large number of parameters to try and get things to work like they 'should' some of this may be what you are seeing.
As far as the timing is concerned, I need TPS or some kind of load feedback to know what conditions the engine is seeing. I assume you are using the stock ignition table correct? when the engine is at very low load [cruising conditions, decel] the timing may be very high. High load- WOT the timing should be referenced from either the high load areas of the ignition map or some kind of WOT lookup table.