I agree Globaliser - when I am travelling on my own account, it tends to be with a ECO ticket and upgraded to PE/WTP ot, as you suggest PE/WTP up to Biz. It is the cheapest way of getting towards the front of the tube.
To check other benefits of BA, check their website. You can find out/ask if the ore-boarding meal is available. This allows you to dine in the exec departure lounge and then sleep more on board. If memory serves, they copied this from VS but I sit to be corrected.