Personally, I’d like for ANet to bring back dual professions but with a twist. You take one of two “jobs” I guess you could say. For example, when I role a thief, I could choose to be an Assassin, which uses combo’s like in GW1 with lead off and dual attacks. Or I could choose to train as a Thief which is more stealth and pilfer techniques.
I say this because I hate the playstyle of thief but I loved sins in GW and I’d kill to play one in GW2. I can see it now, leaping mantis sting to cripple then fox fangs and idk, twisting fangs? Ehhh!?!?
You can come up with your own cross profession examples for fun with your favorite class. I really hope something like this could happen in the future, the only downside is having to balance more stuff, which is imo obviously why they didn’t give more customization in the first place.
I will give a little balance for more fun, hell it’s not like the game is anywhere near balanced right now anyways 
Thanks for reading.
here’s to 1 last shot.