Having experience of both airlines I would say between the two, easyjet would be a fraction quicker but it is very dependant on IF you can get in to EZY. Assuming that you have an Airbus type rating, Jet2 are actively recruiting experienced FOs, whereas i am not sure EZY are recruiting experienced FOs as they tend to draw from their pool of cadet pilots pumped through the big flight schools. At easyjet, especially LGW based, you will fly more than at Jet2 and will hence rack up hours quicker. However that isn't to say that Jet2 would be especially "slow", as once you have the experience then commands are available. At your experience level, between the two airlines, there wouldn't be a notable difference, the question is getting in in the first place.