The only "upgrade" board that I know of is made by Virtue... While it does offer some features and modes that the Blackheart doesn't, frankly, I don't think it's at all worth the $100 when the Blackheart has you covered for 99% of the situations the average player will need it for.
QEV, barrel, and trigger are the only things I consider "musts" as far as upgrades go.
Jay AKA Rogue...
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