Hi! I was in a similar situation to you. Me and my boyfriend play together, and we hit 50 a few weeks after HW came out. It seems daunting, but honestly getting to HW doesn't take too long. We have really limited play time to at most 3/4 hours a few evenings a week because of work schedules, and it took us about 2/3 evenings to do it. Most quests are go here>do this>go back. There are things you'll need a group for, but the DF times weren't that bad really, however my boyfriend plays a PLD so maybe that's why it was fine for us. The longest wait time was for steps, and that was only maybe 10 minutes.

Perhaps joining a FC and befriending a tank to come along with you might help with the queue times?