This is my issue as well. I got about halfway through the PoF story, but went back to play through the whole game in order with my girlfriend, and she's still in Heart of Thorns. I haven't touched Cantha yet. I was able to use a TP to Friend to get over there, but I'd really prefer it if there were an option to flag which expansions you would like to get dailies in, rather than having them randomly assigned based on what your account has unlocked.
Alternately, if there's some concern over people picking easier content that way, just adjusting the offerings based on the latest story step the player has completed would be nice.
Finally, just echoing what everyone else is saying about giving us more options. It's frustrating that we used to need 3 objectives and could pick from 12 (or 4, if you only did one game mode), and now you have to do all 4 (3 if we're not counting the "log in" one) of the ones chosen for you, regardless of what game modes you have selected (which is also annoying - I sometimes dabble in sPvP and used to occasionally do a match to get some of those dailies if I didn't like the PvE ones, but I don't want to select it and be *required* to do both PvE and PvP to get my chest for the day). I vastly prefer the way ESO handles their Endeavor system, where you have 5 daily options and just get credit for the first 3 you do.