Hankyota

Hello everyone, as the title suggests I am looking at replacing the exhaust system on a 87 sr5 truck. I am planning on replacing the manifold gasket, and everything below the "Y" pipe. I have two questions:

1. Is there a brand or kit you would recommend? Preferred materials? I'm in Madison, WI so I've read about some of the benefits of Stainless steel vs aluminum for the rust

2. It currently doesn't have a catalytic converter (looks like PO removed it and welded a straight tube in) and I'm experiencing what feels like a lack of pickup, or low end torque. Would installing one help with that? I've read a lot of conflicting things on vacuums, back-pressure, ect. What I'll be using this truck for is a daily winter driver, taking it up north for deer hunting, and small local haul jobs for my house.

Thank you for any help you can offer, I'm pumped to be a part of the Yotatech community.