There are many threads on here devoted to newcomers asking for pack advice. The answer is consistent. The first thing you need to do is get together everything you intend to carry and determine how much volume you need and how much weight will be in it. Without that information, you're bound to wind up with too much or too little pack.

That said, I would point you to ULA (Ultra Light Adventures) once you know what you need. Luxury Lite might be another good option for you, you can customize it for your needs. Not sure how well it will do on an airplane or a train, though.