Having been EZY at LGW for several years and now LH BA at LHR, there is no doubt in my mind that LH BA is the easier job. More days off and feels like far less work generally.
At EZY, the constant roster changes at LGW were a nightmare. Your 5 days could easily be ripped up on day 1 as crewing had some kind of self induced meltdown and decided to send you off to an airport hotel in TLS for the week. Used your short notice changes? Tough luck pack your bags! I actually once had a crewing officer at easyJet argue with me that the night stop I'd just been changed to wasn't a short notice change because the timings on days 1 & 2 were within 2 hours of my original day trips. Um, thats not exactly the point! How anyone manages childcare is a mystery to me. I simply cannot remember the last time my roster changed after publication at BA (except to have a trip taken off me for training). It may actually never have happened.
That said, I can definitely see the attraction of 75% left seat command at a regional base with easy. Trouble is, as a DEC you're gonna have to put up with quite a lot of the above before you get there. if you do go, for gods sake get away from Gatwick ASAP.