I read with Tarot de Marseille majors-only decks all the time. Firstly, because 22-card decks are very light and easy to tote around. Secondly, because I think there is something that feels very "clean" about using so few cards to draw a successful reading. It's minimalistic.
Marseille majors are very bold and the figures have a nice sense of directionality about them, so I find that they work like an absolute charm. Like many TdM fans, I'm particularly fond of just about any version of the Conver deck. The figures are particularly bold in Conver-based decks.
I don't find that majors work exclusively well with "heavy" matters; on the contrary, I think they're just fine for any question. I read for a friend about her friendship with an ex with a TdM majors only, and it was one of the best readings I've ever done for someone else.
I've also read majors-only with the RWS deck and that works lovely as well. Most decks I will use for readings have 78 cards, but at this point in my tarot study, reading majors-only feels very fresh for particular decks. I highly recommend trying it out, no matter what your question.
You may be surprised.