There are people out there dedicated to collecting all 333 villager pictures. I'm sure they could sell for 55K-99K ish. It really depends on how desperate someone is on finding that specific picture.
If you don't want to keep them then you could try to sell them here or give away for free? Otherwise I'd suggest making a nice room for all them somewhere in your house or museum. Failing that, they could live in your locker forever or you could just trash them/sell to Re-Tail.
I have some spare pictures too. If you don't want to use a room or museum room to display them, or if you've done that, you could use them for decoration in your house.
You can also sell them or give them away. Don't worry about Tiers. There are people who collect them regardless of tier.