Bee, am delighted to learn that Mo has joined you, and to read how well things are going.
Dont be dismayed by the incident where Drum walloped Mo - it's just a case of setting boundaries. Kittens tend to be over exuberant, and it's natural Drum will react by "disciplining the young usurper". This should only be problematic if it becomes default behaviour.
Ross and Dickie are devoted to each other, but Ross (the oldest and the biggest) will often play a little too rough with Dickie. Dickie protests verbally, and gives as good as he gets, but if things get too hectic, he lets Ross know by deftly removing Ross's collar. I have no idea why or how, but this works, and Ross then backs off. sometimes fur has flown in between times, but they'll still be found together later, curled up on the spare bed, a tangle of limbs and tails and contented dreaming.
Just keep an eye on things generally, as you have been doing, and I suspect all will be well.
