First of all, welcome to Flyertalk!

W is a standard fare class used by bmi, SAS, LH and others. Star Alliance carriers have been re-aligning their fare codes to a standard formate. V and W are the among the cheapest economy fare codes.

Your chances of an upgrade are almost zero, I would say, unless you are travelling on much higher fare or are extremely lucky. I fly regularly with BD, and have only ever been upgraded once when travelling on a W fare (and that was on 31 December when the flight was very full).

I have never heard of there being a list for upgrades on bmi. They only ever normally upgrade when there are too many passengers. You can of course volunteer to give up your seat if the flight is oversold, and might be able to get some compensation from that.

EDI-CPH is operated on a BMI Embraer 145 regional jet aircraft, seating around 50 passengers. Apart from the food, the seats in business class and economy class are exactly the same on this plane. Even if you were to get upgraded, the advantages are tiny.