Hi
good idea to get a big case - they are a lot more economical in the long term than the beauty cases so many people misguidedly seem to want to start with
yes the go case should be compatible with any eurorack module
you do however need to keep an eye on cumulative power draw - find the total power draw for your proposed modules by putting them in a rack here - mostly the power stats are ok
the draw should be at most 70-80% of the available power for each rail from thee pus- check this with in the manual for the case or online
this allows for incorrect stats and onrush issues - where some digital modules need much more power than advertised during their boot phase - but may not eliminate them altogether
as for first modules
Maths - it will add more modulation and envelop generation to the neutron and is an excellent learning tool for modular in general - see the illustrated manual, available online - 32 illustrated examples of patch programming it to do different useful functions in modular
a vco and filter - I like Doepfer or mutable instruments for these but if you want noisy then you may prefer Noise Engineering and Schlappi - pretty much anything can get noisy if you want it to!
a quad cascading vca - I specifically recommend veils for this role - especially if you want access to gain - also useful for modulation sources, external input and mixing
don't forget patch cables, maybe a good idea to pick up a few stackcables or headphone splitters for multing signals
"some of the best base-level info to remember can be found in Jim's sigfile" @Lugia
Utility modules are the dull polish that makes the shiny modules actually shine!!!
sound sources < sound modifiers < modulation sources < utilities