Hi, Cindy,
To add what Allan and Jaime have already advised, you definitely do not want to stay in Glasgow the night before a 10:35 a.m. departure from EDI. The M8 motorway, which you'd need to take out of Glasgow to get to EDI, is notorious for accidents, roadworks, and other slowdowns. The A8, which runs parallel to the M8, would take forever. There are several hotels near EDI, and you could spend as much time as you like in Glasgow on the 10th before heading off to your airport lodging.
As far as Oban goes, a lot depends on your interests. If you are walkers/hikers, a day trip to Kerrera would be ideal for the 8th., and you would be back to Gallanach in plenty of time to spend Saturday night in Glasgow. (Cue Will Fyffe!) There is definitely a lot more to see and do in Glasgow (museums, parks, shopping, Glasgow Cathedral, the Necropolis, People's Palace, etc.), but again, Oban vs. Glasgow will depend on your interests.
Several posters here have recommended Kilmartin Glen, which is a short drive from Oban. If you are interested in antiquities and early Scottish history, that could be another way to spend a day.
You have a very short distance to drive from Stirling to Kenmore, and since the games don't start until early evening, you could visit Doune Castle, Dunkeld, and Pitlochry on the way. Dunkeld Cathedral is worth a visit.
En route from Kenmore (I hope that you have made accommodation arrangements for the night of 5 July) to Oban, you could detour via Glencoe to see what all the fuss is about. It's not that far out of the way.
Have a wonderful holiday in Scotland! Your itinerary looks very straightforward and easily doable.
Best wishes!
Mike (Auchterless)