Just a few things I was thinking about as I looked over your rack. You probably don't need either the buffered mult, the ADSR, the Viol Ruina, or the Intellijel Outs. Passive mults will work fine for most purposes, and in a rack this small I would recommend using a few of those star-shaped external signal splitter things. Buffered mults are mainly for splitting 1v/oct CV with no drop. ADSR envelopes would be useful if you are playing with a keyboard, but less useful with percussion. A Quadrax (4x AD envelopes/LFOs/etc.) or something similar might be more useful in place of the ADSR.
I haven't personally found a need for a line-level output module yet, though you might. Just keep an eye on your levels and you should be fine without. More than likely, you will need the opposite: a preamp module that boosts line level signals to modular level. The Viol Ruina is a low pass gate which is good for creating percussive sounds from oscillators and noise sources, but you don't have any of those here. I think you'll be disappointed with the usefulness of that module as an effect with your DrumBrute. Which leads me into this question: What can modular do for your DrumBrute that some effects pedals cannot? Why choose this format for an effects processor? Will you be branching out into synthesis later?
Most importantly, you probably want this to be fun so I would recommend looking into modules that have a lot of CV control. Your delay and ring mod have very little control. The Disting is mega-useful (so I would keep it), but not very fun to use. Maybe take a look at a Happy Nerding FX Aid XL. It's only 6hp, but has three CV controllable parameters and a bunch of effects.
In small racks like this, it's common to try to squeeze in a million tiny modules. Instead, get modules that are hands-on AND CV controllable, which usually means larger. You will almost certainly want a bigger rack in the long run to get the most out of modular. Whether it's the RackBrute 6U or a Mantis... Start planning for that now.
Have fun and good luck.