Hi Rob
Anything that gets, and keeps you in contact with active airline pilots and staff will be an advantage, as exampled in AMEX's reply above. (I think it's a great idea, but don't do it if you're not going to enjoy your work, you may end up doing yourself more harm than good, and you'll spend each flight just wishing that you were at the pointed end).
I tried going cabin crew myself, got a couple of interviews, but got droped immediately they found out about my flying qualifications. The recruitment teams are rightly sensitive about people using their profession as a stepping stone.
Going cabin or ground crew could be a huge advantage. It may not actually get you a job within the same company, but the people you'll meet, and the friends you make, may well be willing help you later.
Good luck...
CB.