Here are a couple of albums by Tamba Trio, a Brazilian group primarily active in the 60s-80s— the pianist I have used on my last couple of records, Jasnam Daya Singh (née Weber Drummond) was actually the last pianist in this group. There are a number of hip Brazilian piano trios from this period doing a similar thing, with all three members singing as well as doing heavy stuff instrumentally. Quarteto Novo, Jongo Trio, Bossa Trio, for example.
A lot of drummers understand nothing but more intensity, and this music is so light it could sound insipid to them. It's not insipid. It's deep light.
Here is Tamba, from 1974:
And Samba Blim from 1968, with an altered lineup called Tamba 4: