It's not awkward leveling 2 jobs at the same time as long as you're not trying to speed run to level cap. I do it with one of my characters. Instanced content I use WHM (including the solo duties because most of them have greatly reduced DPS requirements for the healer roles) and RDM for everything else. In SB both jobs hit 70 within 5 minutes of each other. This expansion they hit 80 same day a few hours apart. Roulettes, side quests, FATEs and hunt bills all added additional XP to what I was getting from MSQ.

There's no need for 2 for 1 jobs when you can already have multiple jobs at the same time.

Make sure you're using your chocobo companion in the non-instanced content. Its DPS contribution is noticeable once you get it to about rank 8 and only gets better as it continues to gain ranks.