Hello Guru's

I've decided to start a eurorack build which I'd like to be part of my existing set up. My biggest obstacle is Wifey who wants to see a clear out of gear before anything new comes in. So far it's been a one way street of new in nothing out but that's not a sustainable situation ;)

Ok so I've ordered a Mantis and I've also picked up the included modules in a sale.

I currently own the digitakt and digitone. Also have the behringer neutron and 303, korg monologue, kawaii r100 drum machine and a boutique tr808.

I'm keeping the elektrons, the neutron and the Kawaii and I want to my rack to compliment and add stuff that these toys cannot do.

I like to make weird arpeggiated beats with atmospheric sound scapes (stuff to play to my mushrooms while they grow) and I love kick ass drum sounds. The R100 is sentimental to me but I own cause I'm a huge industrial music fan.

I'm interested to hear opinions on what the essentials are.
Do I need extra power?
Midi/CV inputs/outputs or will the Neutron cover this?
Amplifiers?

And more interestingly what are the kick ass must have cool beep boop phantasmagorifiers that I should chuck in this rack?

I look forward to your kind responses

Much love