Timeknight has a table with expected multipliers and chest levels, which should help. Not sure where it is, or when it was last updated, but I don’t think it was too many Factions ago.
Intuitively speaking, it seems like Fell Roost has:
Multipliers: Above average/high
Chest Levels: Decent
Team Selection (Purple/Yellow): Okay, not perfect
Leprechaun (), no Rowanne () , Gaard’s Avatar () (Mythic ) (+SQH for 50%), Sunbird (+FG) () (not sure if it’s reliably enough damage the whole way through, might require an extra cast/higher Hoards levels)
Gimmicks: ‘On Death’ summons, which can sometimes be annoying
Path Selection: Okay, but not CoT/HoG
‘Treasure’ Rooms: 1-2, so not spectacular
Overall, good for Delve Chest rewards (Chaos Shards, etc.), but with other factors in mind, I’d still go CoT or Mirrored Halls (no Lep , but great room rarity/multipliers etc., 4 treasure rooms) or SN (roughly in that order). Wild Court’s okay, but doesn’t have good path selection for its treasure rooms, which grates and I think adds up.
Delve farming is not something I do. Monthly 3 day event to max and 1 day events for rewards is all I can stomach. As far as the rest of the month goes, delves don’t exist. That’s how much I despise this mode.
Daily Delve is a good move if, during the week, you don’t have an awful lot of time to play but have a seals goal to meet, then you do long sessions on the weekend. A handful of Delve matches comes with a nice seal bonus!
On the other hand if you’re going to grind for an hour or more yeah, it’s better to stick to the thing you like to do.
Using it is pretty straightforward, if have a handy reference to the rooms for each faction’s delve (that info is annoyingly difficult to find). Just plug in the tallies for each type of room (common-legendary, plus a separate tally for guaranteed treasure rooms) and it spits out the expected multiplier and chest upgrade chance.
The main weakness this tool has is that it doesn’t factor in possible treasure rooms - only guaranteed ones. Do we even know the probability that these rooms can become treasure rooms? This factor would make the calculation a lot more complex, but even a simplified factor would improve accuracy a lot I think.