Definitely agreed with PoppaJo - get that class 1 medical ticked off.
Knowing there's a negative stigma attached to cadets is something to be aware of, but not something that should sway your decision.
Some Check & Trainers prefer teaching and upgrading cadets.
With a cadetship you slot into a system and it's all laid out for you. In G.A you are your own system, so you create your own opportunity.
With a cadetship contract you'll (generally) have all your costs and income laid out in front of you, all the way to an FO's and perhaps Captain's seat, so you can add and subtract numbers to come up with some rough final figures. In G.A. you can only do that retrospectively, aside from initial training costs.
Hope that helps.