I used to have one of those too (well, for zones 1-3 or 1-4 depending on where I was living at the time) but then I moved to zone 2, firmly within "bus-land", and 20 minutes by bus from the office - and it became non-cost-effective to have a full Zones 1-2 Gold Travelcard. My all-zones annual bus pass plus ad hoc top-ups to my card for occasional tube fares works out about two-thirds the cost of a Gold Card.
Despite the fact that I know it isn't worth my while to have a Gold Card (even when you factor in the added benefits like the inclusive Network Railcard and the ability to buy local rail tickets which are discounted by the part of the journey covered by the Gold Card), it still somehow feels like I no longer have the freedom I did when I had one
I know what you mean about it being a key to the city.
It will improve somewhat when they bring local National Rail services onto the Oyster system (at present, season tickets on Oystercard are valid on trains, but ad-hoc fares on Oyster are not), because then at least I won't have to go and buy a paper ticket every time I use a train, which only serves to remind me that I don't have the convenience of a Travelcard.
