maybe an obvious restatement of what you've already seen, look at work by ando or corbusier

zumthor, meier, holl and moneo have also done chapels that you might look at.

Gunnar Asplundh's crematorium chapel has some nice furniture, including a seat that peels away from the wall to form a bench contiguous with the wall surface; and a paving detail in front of the seats reserved for the deceased's family.

Flood Architects & YGT Architects
Xavier Chapel at LMU (Jesuit community)

Custom lighting, etched & laser cut steel grills, font, lecturn, simple upholstered chairs, slate/carpet combo floor, cacti garden

Nicely tied together - old historic building - new modern existence.

link

alvaro siza's santa maria church. absolutely beautiful...though the kneelers look a bit hard. (bring a foam pad)