For someone in their 20s and single, first choice might be OAT NetJets. I know you didn't ask about this one, but others may be interested in how people will rank it. It's the best pay of the lot (I have been told gross pay is almost £50K and net pay is over £40K in year one), NetJets funds the Type Rating and a £60K loan can be repaid in six years due to the tax relief and you can still live comfortably on the rest. If you are married and/or have kids, the six on five off roster pattern may not suit you. This job seems the least likely to get boring or monotonous, but if you don't thrive on chaos or can't be flexible, maybe scheduled airlines are best for you. The idea of flying such high performance jets and the mix of IFR and VFR destinations seems like it would be both challenging and fun. I also think NetJets is the least likely to suffer in an economic downturn and the most likely to win new business if there is another massive terrorist attack, resulting in better job security.
Next for me would be Thomas Cook through OAT. The pay is not as good as NetJets, but still good and you can pay off a £60K loan in seven years due to the tax relief. TCA funds the type rating and it's on a 757. 10 Years to command indicates a stable workforce with very few voting with their feet. They also made the list of top 20 companies to work for in the UK a few years ago.
Next would be CTC. I put it lower than the OAT offerings because it locks you into the airline for quite a few years, while the OAT one's don't. You could leave NetJets or TCA after a year or two with no bond and all you would lose is the tax relief. The upside to CTC is you can get an unsecured loan. If you can't swing the OAT programmes due to not having loan security, then move CTC to the top of the list. The pay resulting from CTC is much lower than the OAT offerings, so if you can fund OAT, it's the better way to go.
I would put the FTE programme last. This is based on my understanding being that all the airline helps with is the MCC/JOC. If they fund the Type Rating too, then I'd probably have to rank it about even with CTC unless there is a bond. I don't know as much about this one, so maybe others will provide info that could move it up the list for you.
My ranking is based on having security plus some cash available. Others will see it differently based on their financial circumstances.