How bad is this?
An Aries who with no air in the chart dating a Libra who has no fire whatsoever. They do have matching moons, however.
Depends on how you look at it. It can be complementary. You two have what each other lacks so that's great for growth! It can be a drag too because there'd be times you won't understand how the other functions and this can cause misunderstandings if communication is not so good.
Me personally is mostly just fire and air in my natal chart. I'm a Libra sun with Aries moon too. For me, heart and mind has to agree otherwise I won't bother. There's a lot of internal battles and struggles but ultimately, it balances out. I'm not as indecisive as most leebs and I'm not so impulsive either.