Powdermonkey,
Be VERY careful how much you let on about aviation knowledge or involvement!!!
Depending on which company you will be working for, there is a real danger that they will be only too happy to use that knowledge and possibly experience for as long as it suits them, and then at some stage, certain people in management will see your skills as a threat, and you WILL get shafted on the thinnest of excuses.
When that happens, you will also get very little help from a union, as it's more than likely that the person doing the shafting will be one of the union representatives, so there will be no enthusiasm about possibly threatening the shafter's position.
I speak from personal experience, be VERY careful!
From a work point of view, it's can be physically hard, often bitterly cold in the winter months, especially on the cargo flights at 0500 or thereabouts, often wet, and at times dangerous if you don't keep your wits about you and your eyes open. You will get masses of training about health and safety, and it's all important, and even more so when you see how some of the older hands will blatantly and regularly disregard the same rules on a regular basis. There was a fatatily at DUB a few years ago when a ramp agent was hit by a prop, and there were still people doing highly dangerous things on that aircraft type despite that incident.
The "average" 757 will have 200 to 250 bags, usually close on 20 Kgs, and you'll probably handle every one of them at least once, possibly twice per flight, and if you're short crewed, you may well end up handling the inbound and outbound bags, and it's supposed to be done in about an hour. That's close on 10 Tonnes!
The working environment at Dublin is dire, as the design of much of the baggage handling areas is diabolical, and at times dangerous!
Be extremely careful of fully loaded baggage containers when going in to the "new" 6 bay off loading area, depending on the weather, and the condition of the ramp, and the brakes of the towing tug, it's all too easy to end up not being able to stop, or get round the bend at the bottom of the ramp, and in the same vein, an LD8 baggage bin on it's side at the exit door of the "new" loading area is also fairly common, and if you're underneath it, it could kill you, as it contains possibly 80 to 100 bags!!!
Be very careful of the condition of equipment such as baggage dollies, cargo dollies and steps. Working brakes on most of these items are regarded as optional extras, and there are many other serious maintenance issues, a while back, a friend of mine reported 18 unservicable fire extinguishers on electric trucks, and a month later, they were still not replaced.
Ear defenders are essential if you plan a long term aviation career.
Baggage handling is the start, depending on which company you go to, you might also end up doing things like towing steps, toilet and water servicing, (usually reserved for the managment stooges), headset operations, pushback driving , and high loader operation, and if you're really good at licking, de icing. You might also be able to get trained on fork lift operation.
The other positions are usually only available after at least 6 months probationary period.
Despite what was said earlier, there are some occasions when you will get to meet and interact with flight crew, but not very often. A lot will depend on the tasks you are doing, if it's baggage handling, then you'll probably not get inside the aircraft, for some of the other tasks, you might, but security issues are making that less frequent.