While the random loot system in DDO leaves a lot to be desired, I love the originality and creativity shown in raid loot; particularly item sets. The item sets obtainable from the Korthos quests and the top end raids are fantastic and obtaining a set is a fun goal that adds a lot to the game. I hope we continue to see item sets expanded and offered at the mid levels as well.
That being said, it seems odd to me that sets are often found in the same raid. Specifically, there are three sets available from the two highest raids in the game. Tharne's, Lorrick's and Levik's are all available in the Hound or Vision of Destruction raids. They are very powerful items so it makes sense that they are found in high level raids.
What I don't understand, though, is the reasoning around putting both items from a set in the same raid. Why not mix it up? For example, you get both Tharne's Goggles and Tharne's Bracers from VoD. You got both items in Lorrick's and Levik's set from the Hound.
If, instead, you got one item from one raid and one item from the other, it would create more LFMs, more interaction, and more interest in running more content. I don't want to imply that players are selfish but there's a far better chance of getting someone to run a raid if there's an item in there he or she wants. Currently, Clerics don't have a lot of item draw to VoD and Rogues have little item draw to the Hound.
Using my rogue as an example, I was obsessed with running VoD to get my Tharne's set but had no interest in running Hound after I pulled a Tumbleweed (which I retired after getting my Tharne's set). However, if I got, say, the goggles from VoD and the Bracers from Hound, I would have been equally focused on both raids and more open to starting or joining raids for those quests. I think it would affect other classes similarly.