I'd agree in the main with @Lugia...

and add only get the isolator if you get clipping without it and can't mitigate that with a pad on whatever you are sending it to... you won't do any damage though - I've used an old yamaha mg10 mixer (cost me £100, years ago) and never needed anything to mitigate clipping...

also I'd consider a tiptop mantis case over the rackbrute - a little bit more expensive, but 40hp bigger, better power supply and most importantly no rack wart!! so more space for modules you actually want!

"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