Dragon Age Inquisition.
I've plugged In around 107 hours so far, I've pretty much cleared most of the sites, working on the Hissing Wastes at the moment. I've got the Forbidden Oasis to wrap up when I find the last 6 shards I need in the Hissing Wastes.
I seem to have found 8 or 9 pieces of every Mosaic. Which leaves 2 or 3 for each one. Not sure whether I'll really plug in the effort to find those.. but I've pretty much covered the "map all regions", "establish every camp", "mark all resources" and "find all landmarks". Just a few missing from all sites.Taken out 8 of the dragons...
Wrapped up the Winter Palace, and the first part of the warden plot in the Western Approach. Have to do the big assault piece and find out what that opens up..
With the sheer amount of quarries and lumber resources you find, and the fact you only need a couple to perform the 3 upgrades of Skyhold you can, I get a feeling that potential future dlc will expand options for what can be done with Skyhold.