I see a lot of hate towards the Duel mode. However, every other mode takes much more time, rewards anything but big collections and tons of talent / free time more, and generally upsets my daily schedule. Some players can get to their ELO mark in an hour or 2, some can play just one tounrey and that's it, but I'm pretty sure most can't. Most players can't get anywhere in survivor and in deathmatch the rewards are not al that exciting and you generally run into all sorts of crap.
So while I'm a veteran and all that, I mostly play duels and do missions in classic (or now in the guild room). This also means I log in every day, check my market stuff, check my guild, and play my daily duel. Sometimes I play some ELO, sometimes I play a tourney, but for tourneys you have to set your schedule by Urban Rivals, and ELO can be swingy and it's hard to predict how much time it will take.
But if you have an hour and want some relaxing play, there's no reason not to do a duel. What's with all the "remove duel from premises" hate posts? I don't see many here, but then the english speaking forums aren't very active, but every other post in the italian forums on any topic is about removing Duel...
An, srry for triple post, but if they wanted to monetize anything that made sense, they shoulda monetized the ability to play more than one duel for more than 3* commons. You'd have pepole dumping credits into that without problems.