For drums and percussions, the possibilities are endless because they depend closely on the musical genres. As the principle of these instruments is basically quite 'physical', it can indeed be a good idea to go for external controllers (as the Beatstep Pro), and even to complete with traditional drum machines. I personnaly use both.
Of course I have reserved some elements inside the modular itself, in relation with the its specific qualities and in order to create more complex drum parts...
So, on the trigger side, I currently use: Marbles, SIG, Varigate (which can be based on chance, a number of steps you determine, and all on several different channels), LB5 (logic module), A-151 (sequential switch), A-160-2; plus Nin (Zadar expander with manual trigs), Ears; and DFAM which has an extreme playability.
But there are also many others possibilities that are popular around pure euclidean sequencers.
As always, a question of taste, priorities and investment :)
'On ne devrait jamais quitter Montauban' (Fernand Naudin).