I'll launch in here:

If you really only want to go 1st (A), you are very limited in route options because many carriers going to the non trunk route cities only offer WHY and Business class. That for a start will cut out all QF Australian domestic flights and about half of their International flights. It also stops you going to IPC for example.

Are you after information on pricing? If so, then there's many ways to get a good value ticket - that's important to most people here.

Some airlines make it very hard to get A class (eg LA) on some routes - even if they fly with empty seats.

Are you after information of seat comfort? There's a lot to read about that. Best seat?

Are you seeking maximum FF miles, status credits, hours in a plane, amenity of airport lounges, ability to use an E ticket, re-issue a ticket, minimisation of airport taxes, what constitutes a transit versus a stopover, who can bend the rules, which is best airline for issuing the ticket, can you get it without buying it in person, name of an agent who is a "friendly", maximum ticket validity, airports with good nearby hotels (for those long stopovers), whether you can do a turnaround on the same flight or even which lounge has the best scotch?

All this and more is here, but we'll only spend our time commenting if you give us a few leads. Make it easy for us and you'll get the information you are seeking.

If you narrow down your questions, you'll get (better) answers.