You know best in what directiion you wnt to take your Rack, if you are thinking of expanding I'd say you can't go wrong with a Marbles or a clone of Marbles. Lots of triggers and pitches which you can keep in tune and remember you cam use marbles as a big weird modulation source with all its outputs.

Enjoy your spare HP, don't rush to fill every last space, this is not like filling sticker books. Resist the urge to 'complete' your rack, its never complete so just relax.

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