We can plot the bid/asks to an extent, and the premiums too.

This is what the orderbook json contains for each order (with a couple optional fields we can deal with):

{
    "id": 31829,
    "created_at": "2025-02-13T10:08:07.472893Z", 
    "expires_at": "2025-02-14T01:08:07.472893Z", <--- can check what doesn't expire
    "type": 0, <-- 0 = buy, 1 = sell
    "currency": 2, <--- see frontend/static/assets/currencies.json
    "amount": null,
    "has_range": true,
    "min_amount": "500.00000000",  <--- could use this for liquidity estimates
    "max_amount": "1840.00000000",  <--- could use this for liquidity estimates too
    "payment_method": "Revolut", <-- looks to be freeform-ish, not sure how useful
    "is_explicit": false,
    "premium": "0.51", <--- looks good for everything I looked at thus far, except XAU
    "satoshis": null,
    "maker": 1234, 
    "escrow_duration": 28800, <--- may be interesting to measure over time
    "bond_size": "3.00", <--- interesting
    "latitude": null,   <--- hopefully NO ONE USES THIS
    "longitude": null,  <--- hopefully NO ONE USES THIS EITHER
    "maker_nick": "xxxxx",  <--- i'd strip this
    "maker_hash_id": "1234567890abcdef...", <--- i'd strip this too
    "satoshis_now": 1994359, <--- i need to reverse engineer wtf this is
    "price": 92260, <--- this is a bid price (because type=0)
    "maker_status": "Inactive" <--- interesting too?
  },