From what I understand EL AL was successful at Stansted and even used it as a stop over for flight to New York. I personally wouldn’t be surprised to see them return to Stansted, same reason as others have mentioned and they can use wide-bodies more often and fill them up. If I’m right a full B772 couldn’t depart from Luton’s runway. Apologies if I’m wrong.
Also when the Tel Aviv flights by Arkia do operate its EL AL staff doing the extra security checks. Though this doesn’t have anything to do with EL AL return. In regards to Arkia they mostly had good passenger loads when operating previously and the easyJet figures and always quite high to.
In regards to Egypt Air I doubt it would be the passenger side, it’s likely to be the Cargo. They’ve operated before and where meant to begin regular service previously and didn’t. Either one would be a nice addition.