Most Prestigious Product Groups

This is the wrong way to look at it. Trading is very different from banking. You should figure out what interests you. Micro? Then you should go for equities or credit. Macro? Then you should go for rates or fx. What type of pace do you like? Slower? Then you should look into securitized products. Faster? Then you should look into fx options. S&T is a very much "on you" type of field. You're not going to succeed unless you genuinely like what you are doing.

As for hours, the more structured the product, the longer the hours will tend to be... There is also an advantage to going to desks that have 24 hour coverage like fx in terms of how long you have to physically be in the office, the book typically rolls. But there's a disadvantage too as your positions are literally 24/5. Do you mind watching the market from home? If that doesn't sound like you, then you should go towards markets that really only trade during US hours.

As for exit opportunities, it's much harder to get into buy-side opportunities other than execution trading if you're doing something like equities or credit... Bankers will always have to edge. However, for macro type funds, the breeding ground is still very much rates or fx dealing desks especially those that let you take prop risk...