Welcome, check out the FAQ called 1000q (1000 answered questions), it is also listed in the stickied post at the top.
To answer your questions, if you already have a chip, a boost controller would help marginally since you have a conventional wastegate style turbo and a electronic solenoid type controller would help keep the wastegate shut until the desired pressure. A spring type manual controller won't be as helpful so I wouldn't spend the money on it. In short, just leave it as is since you say you already have a chip.
to give you some ideas, the blitz sbc boost controllers are probably my favorites ecause they use a very large solenoid and can go up to the high boost pressure that diesels see, 36 psi max. however, it also costs $500.
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