My MIL goes BANANAS. She literally gets each kid about 30 stocking stuffers - enough to fill an entire laundry bag sized "stocking" - plus about 15 "real" presents. The stocking stuffers are things like jacks, pick up sticks, whiteboards, markers and stuff from the dollar store. Lots of junk. The "real" presents are big toys. Art kits, talking globes, mini pin ball machines, etc. We live in NYC within walking distance but have to take a taxi home because there is too much to carry.
My kids get so much stuff from her, none of it ends up mattering to them, and we really don't have the space for it, so we end up donating a bunch. It's not even a real opportunity to teach about giving because the volume of gifts is so huge they don't even care that we are giving some away.
Consequently, we tend to be really low key and try to get things for my kids that have more depth. One Hanuknah I got them a homemade art box. I took a big old Tupperware and decorated the lid, and each night got additional art supplies - paint, glue, paper, brushes, etc. that lasted about two years. Other years I have gotten them books, gloves, slippers, movie tickets, etc. I try not to spend more than $100-150 for both of them all in. Especially with my MIL, the whole thing becomes so excessive it stops being fun, so it just feels better to rein it all in.
For other family members, we tend to spend about $50 per person, except for our parents, whose birthdays/anniversaries fall in December. We do combined holiday/birthday gifts for them.
I am starting to hyperventilate just thinking about the season!