I thought I'd chime in with a couple of thoughts.
Firstly, I'd be a bit hesitant about running insulated supergaiters with Arctis Ex boots, even in June. Chances are good that you'd be fine, but you can certainly get some super cold days high on Denali, even in July... It would be a bummer to regret having not brought overboots.
Secondly, one thing to consider with teams of 6 climbers and 2 guides is what will happen, if someone bonks and cannot go to high camp? We've seen this happen time and again, and having only one guide on summit day can really limit your options.
For what it's worth-- there is one company that offers scheduled trips of 6 climbers and 3 guides. Thanks for the shout out in this thread Scott!