The character data returned from the API is up to ~5 minutes old, so returning HP isn’t really useful. It could technically return the other stats, but computing all that is a bit difficult so it doesn’t currently.
Items with chosen stats are a known issue. There’s currently no way to tell that an item has chose-able stats, nor can you determine via API which stats are currently selected. It’ll get fixed at some point, but probably not within the next month :<
