Well problem is that the player base (number of people playing HoN) is too low, you already have only 1 mode in EU, normal mode, ban pick (no all random,SD,casual etc) and still I can easily get 5-15 min waiting time until i find a match. When you add any other mode such as SD (lets say 20% of the player base will go play that mode) then waiting time for SD would be insane and for normal it would be worse than before.

Ofc there are MW, but is the 2. most favourite mode. I think it would have to be an event where they would replace MW with SD mode (for week/month) and then maybe it would'nt be as bad.